Any wax dissolving solvent will remove enough to make the glue stick. Acetone, turpentine, etc.
I'd use TruOil or shellac over the skins - after scale removal and trimming, then wax over the finish. Skins are nice but I am getting away from using them because they are the weak link. You have to handle your bow more carefully in the brush and can't use it to whack stuff out of your way on the trail.