Sorry you haven't been able to fully resolve the issue.

When you go the shop-vac route - it's important to make sure that the liner is fully sealed [use duct tape to seal where you put the hose behind the liner and tape off any suction and return ports - from the outside of the pool]

With < 2" of water in the pool, if you can get good suction from the vac, it's possible to go barefooted into the pool and work out wrinkles -it's a little tedious but possible.

Thanks for the update and please stay in touch.