Thanks for your suggestions.
The pockets have a new, undamaged curtain of leather from top to bottom.
Yesterday I lined up on the red circle of the ball that is in excellent condition and hit a hard draw shot.
There was a scuff mark right where the tip struck the CB.
I've ruled out the balls.
I don't know what else to try but I will swap chalk for the first test.
I've just been too busy to get to the table since then.
Good question...I recall someone on AzB getting mystery marks on their balls and it would up being a screw head in the ball return track on their Diamond table.
Pro Am is a ball return table? Very well could be something in there. Screw head or something.