Web, it's me (the jewel ) Let me set your mind at ease about the structural integrety, the materials used are fine and being out of level doesn't compromise them. The pool where the collar etc washed out was on the side of the pool that the retaining wall hadn't been installed yet (it was due to be done the week after the rain) (we built the pool on a sloped backyard, the side that failed was the 'exposed side' - hopefully my boss learned to let the retaining wall guys do their thing BEFORE we finish the pool). I believe that your pool is fully surrounded by 'virgin earth, so it's a problem you won't have to worry about
As for the stuff in your post this AM: I misspoke (mistyped?) myself by implying that 1/8" was the point of 'severity', the pools I mentioned were 1+" out of level, what I meant to imply was that 1/8" is very acceptable because the LASER transits we use have a margine of error of +/- 1/16". I can live with myself if a pool is out of level by ~1/4", anything over that falls into the catagory of "what the heck did we do? - over 1" is IMHO 'severe'. Your ~1/2" (sight transits can have a margin of error that much). Your issue is compounded by the tile pattern, if you didn't have the tile pattern to show you the 'unleveldness', you probably wouldn't be able to see it (unless you used Waterwork's advice and got out the tape measure).
It is ALWAYS easier to fix a problem before the deck is installed! However, this doesn't need to be the major fix you envision. A quick fix could involve draining ~1' of water, removing the liner from the affected area, removing the coping and somehow 'shimming' the coping up to level. The problem is finding a suitable material to do the shimming (cedar shims would eventually rot out, metal has to be ~impervious to the moisture found under a pool deck, etc and whatever is used needs to be able to go from ~0" to ~3/4"). But if you can raise the coping to level, the liner will follow.
Having offered a ?posible? solution to fix it, I will say that I would try to get $2000 for the (various) 'appearance damages' (I'd start at $2500 and let myself be brought down to 2000, but why not 'shoot for the moon' and start with $3000?) With that money you could get an SWCG and/ or take DH on a nice getaway (preferably when the deck gets poured - you're not supposed to walk on it for a couple of days right after it's poured). The 'unleveledness' is something only you will notice (your friends etc who come over to swim will just be impressed by the quality and clarity of your water, if you follow the advice posted here!! D) )
I hope I've been able to set your mind at ease and offer some helpful hints as to what to do. As always, if you need a little more on what I've said, just ask