Originally Posted by
SPN Lifer
The safest action and the practice most fully compliant with Marriott BONV°Y Terms and Conditions would be to pay for three people, and check-in yourself, even if you do not actually sleep in the room.
This would be the proper way to do it.
However,
For myself, when I need to do this, I usually just add 1 name to the registered guest name just like OP planning to do.
On some stays, I only register my name (1 guest) and have a friend accompanied me at breakfast or lounge and the staff have no issue with that.
So far never have issue. And I would say only the most pedantic hotel would make a fuss about it.