I'm a big believer, the older I get, in lightening the frustration load, and not dealing with things that give me trouble whenever possible.
That said, your problem(s) could be solved systematically, and both given the custy what they wanted, and you some satisfaction with less aggravation.
I'm sure that you already know some of the advice I will give.
1. pre-shrink your fleece by sending them down the dryer before you even start the run.
2. establish and master your stickum routine for fleece, be it web spray, water-based adhesive, or even those
hook and loop style devices upon which I never quite made up my mind .
3. scan and re-size any problem signatures, or even, take the time to ask the offending signees to re-do theirs.
*note - I usually deal with each signature individually to keep control.
4. Charge accordingly to be compensated for the extra work that fleece, and in this case the art, requires.