What flooring can be used for a gypcrete subfloor?
You have two major problems: 1) Gypcrete is designed to be installed over a wood support, not on gravel or soil, and 2) Gypcrete is not designed to be a final finish surface. That is to say, it’s not made to be walked on...you need a finish flooring, like carpet, sheet vinyl, wood, etc.

Call your insurance company and tell them about your washing machine problem and tell them the flooring (Gypcrete) needs to be removed. Remove it and then install a concrete slab.