The thing about Pathfinder is they did away with level adjustments, so to speak. They base it all on challenge ratings now, which changes things up a wee bit. Not much, but still enough to make it complicated.
I took a look at it real quick with this nifty little app on my phone that allows for customizable races. Making a few minor tweaks (Taking out the Con bonus, removing Zenkai, and removing Oozaru and Tail), I've got it at about 19 RP, which puts it in line with Aasimar, Drow, and a few of the other more "powerful" player races. If you added in Zenkai as it's written right now, that'd put it at about 23 RP, which is more than I like to let players have access to, unless they have a really good story in mind. At 23 RP, I'd guess that could still technically make it a +0 CR character, considering Svifrneblin are at 24 RP and are listed as a uncommon race in the ARG.
As for the class, it's easier to balance that out in my opinion. Change the BAB and Saves to match a Monk, remove the weapons proficiencies (leaving only unarmed strike), and make other tweaks here and there. For instance, I wouldn't leave them with Timeless body, I'd lower the bonuses on the SSJ abilities by half, and implement a system similar to opening the Chakras implemented in Occult Adventures (Ki point cost, Will save and Fortitude save every round, otherwise you drop out of SSJ and become fatigued/take non-lethal damage). I'd get rid of the Fusion Dance, making it a teamwork feat that two or more people have to have for it to work...and there are several other things I would try with it.