If they want to quit, then let them. If bowling is going yo die, I would rather it die with honor by the rules, than to throw all the rules out and have it die as a joke.
People like them cannot be dealt with. They do NOT view bowling as anything other than a past time, and may not even be aware a governing body, or RULES, even exist. As such, they are idiots.
Trust me, there will be someone at the "new" center that knows the rule too, and they (if the kid goes too) will just end up going through this again.
I, As the president of the league, having been made aware of the situation, would feel OBLIGATED to let the other league about the situation and why it happened.
I, as the league president, would also inform the parents that this was going to happen.
Rules are rules. They could either follow them, or get their sanction cards pulled, whichever they wanted.