Levelling a site for an above ground pool with crushed rock???

I would start buy talking to the pool manufactures I'm sure this is a common problem. My thoughts would build a raised pad under the pool. I would make the ground under the area is compacted ( I would guess it is) As for a filler sand might be a good idea just buy wetting it you get a good compaction.

If it was me, I'd go for having the rock removed.

You're going to be putting a huge amount of weight on that spot. I wouldn't trust crushed rock even behind a wall.

If they want more money than you are willing to spend, you could try renting an electric hammer. It's hard work but should be under $100US for one day.

If I understand correctly, you'd planned on excavating to X feet, and did so for most of the pool, and at one end hit ledge at X feet minus about 8", right? ANd now you want to fill the part you've just dug out back up to level with the top of the ledge, and raise the eventual height of the pool by that amount?

The first thing I'd do is take a hunk of re-bar, and find out how much farther you'd have to go to get to solid ledge at the low end. If it's within a foot or two, dig it all out to rock, and then either build the pool to match, (with a deep and a shallow end) or fill with concrete, and get a dead-level bottom that won't move, ever.