I'll tell you what. You go back and get the burl and when you get home shoot me a pm and then I will send you my shipping address. You can then ship the burl to me and I will crack it open and let you know if it was worth it or not.
In my opinion any burl is worth cutting into. I have seen a couple of calls made out of dog wood and they look pretty nice and I would imagine the burl would be nice as well. I personally would not pass up the opportunity to cut open any burl of decent size. Heck I took my boys (7and 9) out Saturday to look for turkey sign and ended up carrying what I believe is a cherry root ball almost a mile out of the woods. Should be some wild call wood from that.
I would go back and get it.