APA says the call goes to the shooter. So have somebody watch any questionable shots. I actually like this because it at least gives you a defense.
I do not like a TD making a call on a shot that he didn't see (with the exception of it being a clarification of rules).
You're confusing two different scenarios.
"Call someone to watch the hit, or it goes to the shooter" only applies to one of them.
Scenario 1:
A player is trying to hit a ball that is very close to another ball, for example kicking a stripe when a solid is very close, or shooting when the cue ball is very close to an object ball and risking a push.
In scenario 1., the foul is PREDICTABLE. You can see the foul might occur, because the balls happen to be close to each other. So it's easy to predict a foul might happen, and you can call a ref to watch. Even then, it might be tough to say what ball got hit first. In that case, it goes to the shooter.
Scenario 2:
A dishonest player is committing an intentional sportsmanship foul. This kind of foul is UNPREDICTABLE because it can happen at any time. He can see he's about to scratch and then use his stick to knock it away from the hole. He can nudge the table to knock in a hanger. He can place his bridge hand and knock one of his balls closer to the hole.
You cannot protect yourself by calling a ref to 'watch the hit' because there's no hit to watch. It's a routine shot, not a close hit. You can't say "well when in doubt, it goes to the shooter" because there's zero doubt. He's flat out cheating.
If you make the rule "the ref has to see it", then he can simply cheat as much as he wants, as long as he knows the ref/league operator is on the other side of the room.
At some point, you have to let common sense take over: if everyone on his team said "yeah, bob cheated", and everyone on your team said "yeah, bob cheated", and 10 spectators say "yeah, bob cheated"... then the ref/LO has to penalize him.