Not positive if they specifically served bud light at the resort bar. I did order a light beer my first night there, but chose the local beer. Frankly, I recommend riding a bike 5 mins into town and buying your beer there at the grocery store. You’ll save $$ and can drink it anywhere on the resort including beach. For the New Year’s Eve celebration we even brought our own booze down to the Beach party. They are very chill there. Very accommodating staff.
Get an answer from Royal West Indies Resort staff and past guests.