Help please with damage from lens removal which caused crazing and stress fracturing.

I brought in my frames to the store because the arm had broken off- about A year old. The tech snapped out the lenses and put them Back in identical but new frames, and now both lenses look like this. Crazing occurred just from flexing them to insert and pop out the lenses, and now the coating has been damaged. Problem is, the store says without use of HEAT it could not have possibly been their fault simply for just moving the lenses. I explained that flexing the lenses absolutely can cause this type of stress fracturing on the coating. It’s Nikon coating so I’m also surprised as well, since it isn’t the poor quality crizal. They refuse to take responsibility. I’ve never cleaned with anything but plain water and a cloth since this has happened to other lenses (but generally crizal and from heat). Ideas? Advice on how to get to store to take responsibility?