Easy, in his suitcases. He was there for 5 days plenty of time to haul it all in. They don’t search your stuff at a hotel when you check in.
He checked in on the 28th- most likely after 3 PM.
The biggest part is that most of those big places are sold out weeks in advance. He had to have had the reservation a pretty decent time ahead-—or IF he was a high roller THERE-—they would have comped him. They always hold rooms open for comping the high rollers.