Too Shallow!!

I had a pool built. It was supposed to be 6ft x4.5ft deep. Turned out to be 2ft 9inchesx 4ft 11inches.
My builder tried to get me to go along with tearing out the lower half and digging down then repouring! And wanted me to believe it wouldn't crack.
Wouldnt it be a seam anyway. There would be no bond right? Unbelievable!
We will start full demo tommorrow............

Oh my gosh!!!!! What a nightmare. Of course, the builder is not charging you for redo correct? All I can say is, take plenty of pictures, and if possible, have addendum to contract for redo. CYA (cover your .......). It makes sense to the builder to only redo half of pool, but I'd also be concerned with seam just as you are.

Good luck.

CaryB