Interference by retired runner

[charliej47]

I was working the bases in a 17U game using MLB with youth safety modifications.

I have R1 on second and R2 on first and B3 hits a deep center field fly. R1 and R2 advance on the catch.

R1 attempts to go home and is caught in a rundown.

F6 tags R1 and starts to make a throw to 3rd base. R1 grabs F6's throwing arm and I call time and announce interference by a retired runner and call R2 out.

The manager comes out and wants to argue that R2 was standing on 3rd base at the time of the interference and he should not have been called out.

I explained that his retired runner interfered with an ongoing play and R2 location had no bearing on the interference call.

Did I screw the pooch?