Differences in league concerning ball and pin action?

Question
In league 10 pin was hit to spare, opposing team member said it hit the gutter then bounced back and hit the pin. Bowler insisted that it was good, that it hit the 10 pin before falling off to the gutter. The opposing bowler did nothing. This was the 6th frame. After the game was done, that opposing bowler left and didn't finish the two other league games.

This is a mixed league. The only bowlers who saw the shot were the bowler and that opposing bowler.

In that situation, having just the two view the shot, what is the proper etiquette?

Sergeant at arms was stating that the benefit goes to the bowler which makes sense but can you please help us on this dilemma? The evening got pretty heated about the situation but if you ask me it was bad sportsmanship for the disgruntled bowler to leave so abruptly and childishly!

Please help! I would like to offer your advice to next weeks league night which is Saturday!

Thanks so much!

~~~Marlene

Answer
Marlene,
I appreciate your confidence in my opinion, but mine is just an opinion. You need to contact the USBC office for your area and they can moderate the discussion and clarify the rules so all sides can hear from the "authority" in bowling.

You can try the USBC website also at: http://bowl.com/rulebook/

Did the shot effect the outcome of the game? Is there some other underlying issue? Thanks for the question.