Originally Posted by
bdelvec
I am in the middle of a Diamond Challenge and getting ready to book a trip to Vegas. I am not sure if nights at an M-Life property would be credited toward my challenge nights so I called Hyatt's Diamond Line. … When they returned they said that the nights at any M-Life property would indeed count toward my challenge.
This is incorrect. @HyattPR has confirmed multiple times on Twitter that only stays at Hyatt properties, not MGM Resorts, will count toward a Diamond Trial.
Those stays at MGM will count toward maintaining your status at the end of the year, but not the trial.