Yes, ask your concierge. Although, now when I add my upcoming stays booked for Sept & Oct to the stays I've already done, I'll be at 47 nights. I'd like to reach the Milestone Rewards since I'm close. I'll probably go for the challenge just in case I end up not wanting to be bothered with 13 MGM Vegas nights later in the year.

I too have relatives in Vegas who I can stay with on the weekends. I highly doubt the relatives could check in for you as additional occupants without you eventually needing to show up with your ID and credit card. With that said I've only stayed at higher priced MGM properties, not the two cheap ones.