NSA Slow Pitch Question Interference or not

[Player Ump]

Scenario is Bases Loaded R1 on 3rd R2 on 2nd and R3 on 3rd. Batter hits ball out to the outfield. R1 scores easily. R2 is coming in to score as the throw from the outfield is coming in. Bounces and gets away from catcher while hitting R1 in the leg while R1 is behind plate area and is helping to bring in the runner from 2nd whether or not to slide. Batter is in between 1st and 2nd on throw to plate. R3 is staying at 3rd. Do I then call out the runner at 3rd as he is the closest one to the plate or do I let it go and play on because the catcher misplayed a catch able ball? Which should be done? Curious as to what needs to be done or what others would have done differently? Any and all critiquing is appreciated.