I was there (Schottenstein Center) last month with family for my son's graduation. It was packed to the rafters and this was a winter quarter graduation. That being said, June graduations are held in Ohio Stadium which holds around 105,000. It a BIG school. Based on the photos from the perspective of the ample backside of Frau Eat Right my guess is the crowd was under 10,000. The two upper decks make up more than half the seating. In honor of Her Thighness, here is the seating chart for a Monster Truck rally:
Thanks for the research, and congrats on son's graduation !
I prolly should've done this to begin with.
Found the seating chart for the setup that was likely in use for the maggØt's event.
Given the photos we've seen, and the floor appearing relatively empty, I'll bet that your 10K guess is a lot closer to reality.