"That's what I do best. Except perhaps the 'before' part. "

Muminofrah
Your host is busy petting Tabat's arm but laughs appreciatively at the obvious comradery.
After about an hour, the course is ready, and the cards have been secured to the camels. Andromeda likely doesn't appreciate that much, but all of the camels seem down right grumpy.
The following is a fair bit of back and forth, with 13 stages to the race. For the purposes of PBP, let's condense it to groups of 3 checks, then a big finish.
Either the driver or the side person can make the check. Let's see how many successes you accumulate over the race.
1. Crowded Start
A score of brave (and some nervous) charioteers line up at the start line near the wharf where Muminofrah’s barge is moored. When everyone is ready, Muminofrah blows a kiss at her paramour and throws a thunderstone on the ground, signaling the start of the race.
You can either Jockey for Position (roll either Handle Animal or Profession(Driver) DC10), or you can Scream and Dash (Intimidate DC 15).
2. Excited Spectators
As you make your way down the street, the spectators that have gathered crowd the street, becoming obstacles for the nearly out of control chariots.
Make Way! (Intimidate DC 20) or Entertain the Crowd (Perform(any) DC 15).
3. Bridge a under Construction
While a holiday had been called that didn't mean all construction was magically finished. The course goes over a small bridge that is only partially safe to navigate, and certainly not at great speed.
Find an Alternate Route (Knowledge(Local) DC 15 or Jump the Gap (Handle Animal DC 25)