I've seen people hypothesize about keyless check-in, but it's always said to not work. I don't know how they manage to not credit it, maybe a gps location required for check-in or something. So confirm it works before booking a bunch of non-refundable rooms or relying on it for status.
Living in Saigon, I've done mattress runs a few times for people who mention on FT they are looking for someone. Mostly it was a few years ago when Accor was offering a large number of Aeroplan miles per stay. They add my name to the reservation, then I am the one who checks in and just mention something like "oh they'll be arriving later". I confirm that it's in their profile not mine for the stay, and it has worked fine. I suppose there is a small risk to them, since I was given some of their info on the paperwork copy. But so far no troubles.