I can't see "good" "steak" and "<$100" being in the same answer.
A good steak + 1 side, glass of wine, = $100 at a decent steakhouse on the strip.
My (admittedly limited) experience of 25ish table gatherings is that the cost of drinks, dessert, appetisers, included gratuity, is all going to nuke your budget when they could be looking at $50 for the steak alone.
So I don't think you'll do it on the strip. Circus Circus would be a very good steakhouse at a low cost, but then you've got to ask all your guests to go to Circus Circus. Going off strip to some of the older joints that serve "steak dinners" (rather than a la carte) might do it. But then, you have to troop 25 guests off strip, so getting out a few miles off strip will have problems. You might be able to pull it off though, under the cover of searching for 'old vegas charm'
Most of your guests will probably call it correctly though as a damage limitation exercise. I'd be tempted just to pick your fav on strip steakhouse, finding out what the damage would be, and seeing how big a chasm away from your budget. Some places have very nice private dining room for larger groups, but I imagine they expect to make considerably more than $2500 out of a booking.
If the quotes make you realise your budget is never going to get anywhere close, then you can start looking at family style Italians