Well, I have never tried that before, but I would guess that you could use a 5-minute epoxy and fill in the ends of the radius and ulna that will be in the overlapping joints of the call. Let them cure thoroughly and drill a hole in the epoxy that is the same area as a corresponding hen wingbone. It may take some experimenting, but it may work. I would think that the resonance of the wild turkey wingbone may be effected by additional internal material, but it may not. Just don't put a lot of additional epoxy in the bone.
On a related subject, the tone of the wingbone call is a delicate balancing act of bone length, the age and physical condition of the turkey, the level of humidity and how the bones were stored, cleaned and whitened. Ultimately, the "sound quality" of the call depends on the prowess and abilities of the caller. Even a Stradivarius violin can render a squawking racket in the wrong hands.
