Trump was gracious.....helping her out to have some fun in the pool.
I got the idea from the other posts that she was there to promote herself as a bikini model. She had some previous bookings and was in a hurry and forgot the bikini. So he lent her a suit so she could hang out and look good, hoping for some future work.
By all accounts, he was being very gracious, and he seems to have a history and habit of being very gracious.