Homer,
VDP is being discontinued, and I guess it's because it's a solution that fails to take backup in too many situations. As you've already tried storage vmotion you've already tried some troubleshooting options and you've probably seen these articles as well?
As VDP is basicly Avamar you can also often find answers when searching for Avamar instead of VDP.
Sorry I couldn't be of more precise help. Good luck!
Lars