Pics of damage, need advice on wall damage

[Mom2Czars]

That wall is fine, however, it tells me the ground under it isn't - it needs to be PERFECTLY level - which it definitely isn't.
I would install a sand cove with a ring of vapor barrier taped to the wall and laid on the floor onto which to build the cove - it'll stop any attempt at wash out...

That is the side where the seams let go and all the water rushed out, so I'm sure the ground underneath is pretty wrecked. The wall doesn't appear buckled like that elsewhere.

[matt4x4]

Just wondering if possibly, the liner was installed somewhat offset, adding downward pressure to the wall there (thus the crush buckle as well as the stress tear in the liner...). Do you remember if your wall/floor seam on the liner was relatively even all around, or was it further from the wall edge in certain places?
Just like the hoffman's pool, liner was off center, one side would not stretch to fill space behind liner, liner thus pulled wall down. In your case, it may well have filled the space behind it, meaning the liner had just enough stretch in it, but was stretched to it's maximum capacity, winter shifting may have pushed it beyond it's limits, thus it let go.