As many International hotels do they will likely request your friends
passport at check in
Make sure after adding the second name you get a copy of the booking
sent to you with the added name on it
There have been times with both Hyatt and Marriott have not gotten the
second name on despite saying they had

In one case my family member sat in the lobby for 4 hours
I prefer Hilton and IHg when adding a second name you can do it right online when booking
Marriott and Hyatt and are a pita when adding a second name and Marriott even worse