I think you are presuming quite a bit here, and I do have some experience in working on sports/entertainment ventures such as this.
First, if the Tropical Park site plan goes through, he will not own the facility outright. Yes, he may be the one to secure the management contract, and yes, he may buy some surrounding land to be converted into an "entertainment area". And, sure, some can claim that this is going to be a sort of year-round venture, but I'm not sure how much revenue will arise (at least on the stadium portion). Look at your own post, you are talking about "state HS football championships". Uh, yeah...how big are those?
Look, if you put a football stadium in Tropical or a soccer stadium in Melreese, those projects are being sold as "seven" or "seventeen" games/matches per year, with the rest of the year devoted to community events. Concerts are still going to be held at Hard Rock and AA Arena and Sunrise. If you tear down Tropicaire and build something new, that could happen independently anyhow, 7 UM football games won't suddenly make-or-break that entertainment area.
Ruiz will absolutely make a donation. He wants his name on the building. He may also be looking for ancillary income associated with the project, but there will definitely be a donation.