Adding concrete on top of Gunite to raise water level

Our builder made an error on the water level. A tanning ledge was supposed to have 10" of water and it will only have 6" with no easy access (it is in deep water) I will compromise with 8" and in order to raise the water level, they (the builder) proposed adding two inches of concrete on top of the gunite to raise the level. The concrete is just troweled on without any reinforcement. Decking will be laid on it and I fear the concrete will shift or that water will seep through the less dense concrete. The permanent water level will still be below the applied concrete but only by 1 inch.

The also missed the location of two drains and had to chisel out the gunite to move them. When I asked if they would leak, they said they would use a special patch concrete and they do it all the time...

any thoughts?

I think I have this right.

1) The entire pool was shot 4" to low or is the ledge 4" to high.
2) The tanning ledge in the deep end will now be to hard to access.
3) The pool will have a concrete deck with a cantalever edge at the pool.

I am going to assume the tanning ledge was built 4" to high. For better access to your tanning ledge have your pool builder shotcrete a seat/step ledge 6" down from your existing tanning ledge and boarder the entire ledge.

I would not add 2" to your pool bond beam if you are going to install a cantilever concrete deck. It will at a later time develop a crack in the tile along the seem between the two concretes. Also your skimmers will no longer be at the proper elevation. If you do add 2" to your bondbeam do away with the cantilever deck and add coping you will also need to add 2" to all of your entry steps into the pool and add an extra row of tile so your water level is not at the bottom of a 6" tile (looks odd).

Hope this helps.