The pass says just President's Club? I'm going to guess no on RCC, since otherwise Chase would state it (if you had an actual PC membership, I don't think there'd be any question), but you should phone UA's RCC number or the specific club you want to access or Chase. Are you going to an airport where there's an RCC but no PC?

I wonder if the reciprocity is more than it was before. A year ago we were flying Biz-First class from GRU to IAH, and were able to access the RCC at GRU (there is no President's Club), but while we got the usual free snacks and drinks, the receptionist said we could not use the showers in the club, stating that those were for United passengers only.