Well, it’s been quite a while since we lived in St. Petersburg. We had our boat at Bayboro Marina, not far from the Vinoy Basin where your marina is located. Vinoy Basin is open to the east, which means it is open to the fetch across Tampa Bay. With easterly winds, which are the most common ones, small seas and wind waves roll into the basin. Any boat anchored there overnight, which used to be permitted (don’t know if it still is), or otherwise, gets to rock and roll. Personal observation and experience. It’s not pretty. I don’t know if the hotel has done anything to further protect its marina’s slip area from incoming “seas.” But if not, you might experience the same boat movements as anchored ones although those are typically more exposed to the opening.
The marina was actually installed so it was rumored, for folks w/big power boats to drive up from, say, Sarasota, park at the marina, and then get a room at the hotel to spend the weekend, or whatever. I doubt you’ll be happy there on the long term; BUT, it could work for a short-term solution to your problem. With westerly winds or calm, the basin is fine.
Further advice: get on the waiting list, if there is one, at Bayboro. If there is a current availability, choose it over Vinoy.