The runner on first base (R1) is stealing on the pitch. The batter (B1) hits a fair high-pop near first base. As R1 retreats toward first base and the first baseman settles under the pop-up, R1 unintentionally runs into the first baseman and the umpire correctly calls interference on R1. However, the first baseman is able to recover and catch B1's pop-up -- while R1 safely returns to first base.

 

One of the coaches of the offense (likely R1's parent) thinks that B1 should remain out and R1 should remain at first base (since R1's interference did not prevent the defense from completing the play).

 

Another coach of the offense (likely B1's parent) thinks that R1 should be called out for his interference and B1 should be awarded first base. Of course, the defensive coach argues that both R1 and B1 should be called out (R1 for his interference and B1 because his pop-up was caught).

 

What do the umpires do now?