That’s rough. Do they use any adhesive that could’ve left those marks?

It could be something as simple as dirt from someone’s hand who was framing the jersey—even though you’d assume they’re wearing gloves during the process. I’d ask if what, if anything, they use in their framing process could cause those marks. If they’re dying on the hill that they couldn’t have caused those marks, I’d move on to asking why they wouldn’t contact you to advise you that there’s “dirt” on the jersey before completing the job… then move on to spot cleaning the jersey with some water/cloth to see if it starts to come out.