Excellent discussion! Thanks debeau. Even the experts disagree. Again we see the value of this board. So now I know what I'm going to do if it happens to me. I'm going to kill it and call it foul at the point of collision.
As Mike said, I'm probably going to have to explain my decision to a coach. Offense shouldn't have to much to gripe about. (The other option was interference and an out.) If the defense comes out to talk: "Coach, you can't have interference on the runner on a foul ball."
"But Blue, it rolled fair!"
"It was foul when I killed the play, Coach. Let's play."