The Royalton web site is quite specific on what you get (and don't) as elite:
https://www.royaltonresorts.com/freq...sked-questions
WHAT STATUS DOES A MARRIOTT BONVOY MEMBER NEED TO ACCESS THE EXCLUSIVE ELITE AREAS?
Marriott Bonvoy Platinum Elite, Titanium Elite, and Ambassador Elite Members have access to exclusive beach and pool areas. To receive access to these areas, these Members will receive an exclusive bracelet
WILL I RECEIVE AN UPGRADE TO THE DIAMOND CLUB™ LEVEL IF I AM A MARRIOTT BONVOY ELITE MEMBER?
No, Members need to purchase Diamond Club room categories to have access to the Diamond Club . Note that Diamond Club™ categories are not available through redemption, only regular bookings.