My post will not be helpful probably but my daughter was in your situation 3 yrs ago. She was accepted to the Dual program with Columbia/Sciences Po in France (does not know French) and to Brown. She chose Columbia but ultimately did not attend as went to Oxford where she was also accepted pending the results of her AP exams.
FWIW, she really likes the social life in Oxford even during the pandemic. I guess, living in Dublin will be equal fun. Moving to Ireland, however, is logistically more difficult, especially if you need a visa (my daughter did not). If it were me, I would choose Brown for her but I am just a mom.