Welcome to FT, Pearl13!

This is pretty standard, I have to say. I've booked rooms for friends on my card, and on more than one occasion booked a room for my wife when it was just easier for me to do it even though she could have used her identical credit card. Just have your uncle call the hotel to tell them that you'll be the occupant, not him, and this should be noted on the booking. If you're really paranoid, have that confirmation sent to your uncle which he can then give you you. But in short, don't worry.