There is a leaking spot on the floor of the skimmer inlet (Please see the pictures attached, sorry the pictures are upside down, and I failed to figure out how to turn them around). It lost 2 inches water per day, and was detected by injecting coloring. The leaking spot is on the left hand side, below the fiberglass and above the tile/skimmer. The pool is is a concrete pool. I guess there was a leak, and the previous owner used some fiberglass to seal it. Unfortunately, it started to leak again. The pool company asks for $700 to fix it by cutting the fiber glass and seal it with some kind of concrete which I don't quite understand. They said the previous fix with fiber glass is not professional at all. They also mentioned that if they can't cut the fiber glass without damaging the skimmer, then I will have to pay $2500 in total to replace the skimmer.
The price sounds too high to me. I am wondering what is the best way to fix it? Can I just remove the old fiber glass, and patch it with some new fiber glass or some other materials.
Inputs are highly appreciated.