So to break down the process.....
The play is killed after the interference. We call R1 out for Interference.
So far, so Good, everybody is happy
Then PU comes out and says, I have CO.
So we get together and enforce CO, which would give the coach the choice of taking the result of the play or putting BR on 1B and moving everybody that was forced to move up one base, which would put R1 on 2B
Do we agree on this, for the most part.
and either way, we got some explaining to do to a coach