No, we're not really expecting Matt Olosunde to make his Premier League debut for Manchester United in this game. Jose Mourinho provided a long list of young players he expected to feature in the squad for this match - and Olosunde's name wasn't on it.
So chances are this is just a meaningless end-of-season game for Man United, with no significance to the club's Premier League standing this year (it has already clinched sixth) and little interest for New York Red Bulls or USMNT fans (Olosunde is a former RBNY Academy player and US youth international).