[Heel n Toe]

Ask the foreman if he will let you go buy better skylights in the same size and bring them to his crew to install in place of the junk ones.

Even if they've already installed the junk skylights, get a price from him for taking them out and dropping in the better ones. Even if they've already flashed them and put the new shingles on that area of the roof, it wouldn't be a huge deal.

If he absolutely refuses to do it, just let it drop, but get them to leave a couple of extra bundles of shingles with her when they finish the job... they usually order plenty and have some overage. They may be planning on leaving extras for her anyway for future repairs that could be needed.

If they balk at leaving extras, just find out the specs on them and go buy a couple yourself. Then after this guy has finished and cleared out, call another roofer to come give you a price to install the better skylights, and let her decide if it's worth it to her.

You/she could maybe sell the junk ones on Craigslist, but she might have to eat them.