Wow! That will be one hefty bill for 25+ people!!! Yikes! I assume that you can get the PAP 15% discount for the whole group, as log as there is one bill. I don't see why they would not do it. The problem would be if you broke up the bills and people paid separately, and then you tried to use your PAP discount for one of the guests without an AP. Otherwise, I should think it would be no problem.
PHXscuba would be a good one to comment here. PHXscuba went to Goofy's with a large group (though not as large as your group) for dinner in October, and I would hope someone used an AP for a discount for everyone. You need a discount when you have that many people!!