Automatic cover track problem

We are building a 20' x 34' in ground pool with concrete walls, vinyl liner & auto cover. The cover company came today and installed the track. I had to leave for awhile and when I came back they informed me that the concrete walls were not straight. They bowed out in the middle about an 1.5". I call the PB and he said he never had a problem like that before and the .25" foam under the liner will cover it. That doesn't sound right to me. If the track is over hanging the walls in the middle .75" on each side then there will be a .5" space between the foam & liner. Also this will be up out of the water by the top of the pool. The tech from the cover co. said the PB should flash cover the walls to fill in the gaps. I'm worried if that concrete or cement will adhere to the existing walls. If the PB won't fill in the gaps I was thinking of having him sign a guarantee in case the liner rips. I was also thinking of calling the liner company for their opinion. What do guys think?

PB said it was no big deal and that the corners are going to have even more space, 3" to 4". That did not make me happy. He said if you want tighter corners I could have gone with radius corners but, not with an auto cover. I ask him why he didn't tell me this in the first place before when we were designing the pool and I could have used radius corners with the cover company I was using. He even threaten to walk off the job. Then showed me his pool which didn't alleviate my concerns at all. Since he had a big chunk of my money I knew I was screwed. Wife just wanted it done so now liner is in and pool is opened. I can feel spots under the track in the middle where it's not tight, just hope it holds up. Maybe I should have gone gunite.