Dogs don’t mind new places. They mind new places at bedtime. All day the hotel is an adventure; around 8pm the adventure is supposed to end and nothing smells like home. That’s when the pacing starts, then the whining at hallway sounds, then the 2am bark that gets you the front-desk call.
The fix is boringly practical: arrive with a dog who’s already tired (the long walk happens before check-in, not after). Set up their bed and one unwashed item of your clothing before you unpack anything of yours. Feed dinner in the room, in their own bowl — eating somewhere is the fastest way a dog decides it’s safe.
Then do the fake-leave: step out for two minutes, come back before the worry starts, repeat once. It sounds silly. It teaches the one lesson the room needs to hold: humans leave and come back here. Most dogs sleep through night one after that. The ones who don’t usually have a human who skipped the walk.