Ocean City Maryland Fager's Island-Underage Girl in Bachelorette Group

I have planned a bachelorette party in OCMD for May 15-17. 5 of us are overage and 1 is 20. We will go down the boardwalk Friday night with the older girls probably popping in a few places for a quick drink and everyone shopping, chatting, etc. On Saturday night, I saw that Fager's Island does a cool scavenger hunt with a gift card for the bride at the end. I think this would be perfect for us. However, one member of our group is only 20. If we go to Fager's for dinner, does anyone know how it's set up and if we could then go to the bar area(s) for the scavenger hunt part? We are not trying to sneak alcohol to the underage girl or anything, we just want to have her there. I'm wondering if going for dinner sort of "gets us in the door" to do the rest of the activities. I've never been there. If we go before 10 (when minors have to be out) will they let her in? If not, do you have any other suggestions of what to do with an underage member of our group?