New Pool Leaking, Backfill sinking, Water under vermiculite?

[leakynewpool]

I am still in the process of getting my steel walled, vinyl liner, vermiculite bottom pool built. Just before concrete arrived on Thursday, the contractor noted that the pool was losing water and ALL the backfill was sinking toward the pool. He found and fixed the leak, but my husband has found "soft" spots under the liner. Did the water leakage seep under the liner and degrade the newly poured vermiculite? Is this a problem that is possible. There is a concrete footer all around the base of the pool on the outside, but couldn't water leak under there and cause problems? What do I need to make him fix before he pours the concrete decking around the pool and seals in any future problems? HELP!!!!