Need opinions on which lens to use

I have a gig shooting a belly dancing show.
Its in an auditorium with stage lights and I have all three of the available options for shooting.

1) close to the stage on the floor shooting up at the dancers (which is what I will do unless the ceiling is a really bad background)
2) on stage shooting from the side ( not a good option because of the background on the other side)
3) in the back shooting with a long lens.

If I'm in the back I'll be using the Sigma 50-500 superzoom no choice there.

my question is if I'm in the front should I use my favorite Sigma 18-200 that is f3.5-6.3 or my old faithfull Vivitar Series 1 28-105 f2.8-3.8

under the stage lights I'm thinking the slower but much wider and longer Sigma would be better

What do you guys think?

If it can't do the job, I'll have to improvise ( perhaps go beg the light guy to lighten um up a bit).

So I guess you just talked me into taking all three.