I once saw 2 bizarre fouls once in the same tourney and your scenario reminds me of this. The first one, as one of our opponents (good player) was walking around the table, he dropped the chalk and it landed on the cue ball and moved it a little bit. We got BIH and ran out. None of us had ever seen this happen before and we didn't know what to do. That's how the tourney director ruled The 2nd one was in the finals and this one was even more strange. It was a tight match and our opponent (600 FR roughly) was at the table with an open 8ball layout. He was mapping out how to run the balls and putting his cue tip on the table from shot to shot connecting the dots you could say as some people do. As he was doing this, the cue somehow fell out of his hands, moved like 4-5 balls, including the 8ball and ended up resulting in a loss of game. We won the tourney, but both matches with the fouls were tight and may not have happened without out it. Not sure if I'll ever see either of those things again amongst decent players.