If the paver doesn't extend very far under the upright, I wonder if you could just tap it down with a board and a small sledgehammer. The weight of the pool pushes on the ground under the liner. It is not supported (in the vertical direction) by the uprights. The only weight the paver should be supporting is the weight of the wall, the upright itself, the top rail, and someone who decides to sit on the top rail. This is why I think you might be able to tap it down. FWIW.
Tom