Super dry material that has been washed with butane already is not likely to squish rosin even if it has residual resin leftover. This is because the resin has been washed over/through the nugs, being dissolved along with the glands that contained it by the solvent. There is going to be next to no residual moisture in those washed flowers to aid the rosin squish and there is far, far less resin per square inch of surface area to get out of the flower to begin with! It is like trying to squish lightly vaped AVB. Too dry, not enough resin = no dice!
The best thing to do with herb that has already been washed is wash it again with a solvent. This will get any leftover resin off of the material and if your wash technique is good, it should still be bearable to dab!
Dry sifting solvent washed flowers is useless. The resin glands dissolve in your solvent and so sifting off the remnants of the glands is not going to help you much.
Bubble washing material that has been solvent washed is similarly a fruitless effort for the same reasons.