Sounds like a problem…moisture that is underneath the flooring will probably start to mold I would think, and could also cause the Pergo to delaminate if it’s really wet. Pergo is basically an MDF-type product faced with laminate, and is not intended to be used in damp locations such as bathrooms, etc. Are you sure it’s squishing from moisture? Pergo is installed over a layer of foam cushioning…could it be the foam that is squishing? Does it happen everwhere you walk? Just some ideas…