Could use a little help please!

Good morning/ afternoon/ evening..... Greetings everyone!
I'm just looking for ideas for my D&D campaign. I had them start as prisoners on a ship being attacked, they are first time players and this gave them a quick combat experience, the ship sank and the PCs are washed up on a beach. They began walking trying to find other survivors or some help. They met a local who informed them that they saw the wreck but no other survivors had washed up yet. Through talking it is mentioned that the Lord on the island is trying to get a crew together for a ship to voyage back to the mainland with his wife's body as she was orrifinally from there and wished to be put to rest in a family plot. They began to make their way towards the Lords manor, a several day journey, as snow begins to fall and make a stop in a town as night began.
Now that you are all caught up, I would like to introduce you to the conclusion for my campaign. The players get the Lords wife's coffin onto a ship with several crates of her belongings. They can either board the ship or stay on the island with a note from the lord saying thank you for transporting these things for him, however they are not her belongings but dirt from around his manor and the coffin. Is not his wife's, it is his own. He thanks them for transporting him to the mainland to begin a new empire, an empire of vampires. This would create in my timeline a rise of vampires and a decent into a post apocalyptic setting for later campaign(s).
But here is the thing, I'm not 100% sure what to have players do in between. I am thinking perhaps that while the PCs sleep the snow continues to fall and it get to a point where the PCs can't make a safe treck through the hills/ mountains to the Lords manor. They would be stuck in the town and surrounding areas. Perhaps people have gone missing in the past and/ or are going missing. If they return they are extremely tired and pale and don't remember what happened, and at nights they disappear again.
Though that feels rather weak and railroaded to me. What does everyone else think? Is there anything else that I could have them do instead or as well?
Thanks in advance all!

I'm not entirely sure what you're talking about in that last paragraph... So the vampire lord made the players vampires or something? Also, snow? where did that cam from? Were the players sailing in winter?

I think you need to foreshadow the vampire stuff, it seems like a big plot point for you. It's a bit confusing why the players have to transport the Lord's body? Unless I misread that lol.

Maybe think how the vampire lord affects the towns. If people know about ye vampires. If people are being manipulated by him. Is he a powerful vampire? Is there anyone actively hunting him?

I can see the campaign going well if you give hints about the vampire. Then your players can decide to help him or kill him or just dip all together. When and how you handle this is the fun part lol

I'd roll back and ask you a few questions. Why does the Lord need to leave the island? Also how made him a vampire? If he's in charge and a vampire (I would assume slightly stronger than a noble at least) why couldn't he slowly make an island of loyal day time watchers/guardians? If he's leaving there's likely something better someplace else for him he's researched or he knows someone is going to come to the island and hunt him down maybe.

It sounds like there are those loyal to the lord of the island in your setting, is everyone on the island loyal or is there a split? Is he leaving so there isn't a civil war? Is his wife actually dead or in hiding until he leaves and will take over as a normal human ruler?

I do agree with others that there should be some clues to things being off so they look into the Lord and possibly find out he's a vampire. The thing about a story the GM has in mind once the players see it things will likely change for what you're planning. It's entirely possible someone will suggest killing the Lord (regardless of if they know he's a vampire). I'd have the people or the Lord help the PCs so they're invested in guarding the island or helping possibly maybe set up an NPC to constantly be helping them with minor things end up missing in the winter when the snows get heavy.

Good Luck.

I like the idea of giving them a likeable npc then killing him lol. My party stole a goat once and would just bring it around as a pet. She went missing at some point and it was a big uproar. They made it a whole subplot. The Quest for Sheela.

For GMs there's railroads and puppet strings... the best strings are the one's the players put on themselves without noticing.

Interesting story so far, Mr. Unknown6425.

I agree with what people have mentioned about puppet strings and foreshadowing. Lots of good advice on this thread.

I'd make vampires a common monster type to encounter on the island. Consider using Sly Flourish's vampires for a greater range of CR and types of vampires (all well-balanced) to challenge parties of any level.

I'd put in the following areas and suitable NPC hooks to get them moving.

Vampyre Tomb

There is a certain dark abbey deep in the woods that the locals know not to disturb. Within the last year, an adventuring party arrived and foolishly attempted to loot the evil cathedral. They were never heard of again, but ever since terrible things are afoot on the island. Rumours have it that the adventurers awoke an ancient evil. If the party goes here, they find a vampire nest consisting of some of CR appropriate vampires, perhaps human captives, and evidence that a powerful being was imprisoned here but is now free. They should definitely be left with the sense that they should GTFO of this island.

NPC links: A plea to help find missing townsfolk, rumours of treasure in the dark abbey,

Shipwreck Salvage

There is one ship on the island that might be made serviceable again and allow the party to leave; a moored ship that the doomed adventurers arrived on. Barely seaworthy, but infested with vampires and other CR appropriate undead. Maybe you find zombie versions of the adventuring party here for a fun encounter.

NPC links: Many villagers would love to leave this godforsaken island, and know of the ship. The lord himself offers assistance to refit the ship if your heroes can liberate it from the monsters, on the condition that his wife's remains must be ferried on the first voyage.

Dark Paladin

The creature rumoured to be released from the abbey is an evil Paladin that preys on the village. The villagers believe she was once the village's protector who was turned evil by eldritch magics. She was released from her prison when the dark abbey was disturbed. This is the false BBEG of the game that distracts players away from the real BBEG.

The truth is that this being was once a vampire hunter who sacrificed herself to seal the vampire lord within the dark abbey, and was released along with the vampire lord by the adventurers who stole into the abbey. The vampire hunter is now herself a vampire and does indeed prey upon the villagers. She still crusades to destroy the ancient vampire she sacrificed herself to contain, and is willing to use and destroy anything for that goal. For example, she plans to contain the vampire lord on the island and kill all the living inhabitants to cut off his food supply.

The vampires that guard the shipwreck were in fact sired by her, and are there to prevent the lord from escaping while she hunts for him. She likely does not know that the ancient vampire lord masquerades as the village lord. A confrontation with the dark Paladin could make a good ending as she leads a final attack on the repaired shipwreck to keep her ancient foe contained.

You will need to come up with a reason why the vampire lord hasn't just dealt with the Dark Paladin and her minions. Presumably the lord is still deeply weakened from whatever imprisoned him.and the dark paladin is real threat to him.

I hope that some of this makes sense and is helpful to you :)