Apologies for necroposting, thought it was better than starting a new post.

I have a similar dilemma. A friend booked (directly with Marriott) a couple of rooms for a trip; so the rooms are technically in his name and I am an additional guest. I went to the FD earlier today and asked to add my number to my room. The FD gladly did it.

Question: Will it sync up to MARSHA so that it shows as a current stay in the app or do I just hope they did it right and I will get the credit. It is a 7-night stay, so I do want them to credit 🙈