Rig and Skin 2 character models

The issue is Unity does not support Twist Bones. I have 2 human character models that were originally rigged/skinned with Biped using Twist Bones. I need a tech artist to take an existing character model that is rigged with Biped in a 3DSMax scene, remove the twist bones, skin the weights correctly, and produce a clean Biped skin model I can export as a FBX and use in Unity. The completed model should be properly rigged and skinned with no twist bones (or any other unconventional method).