The dog ID for the jaw could be right, but I doubt that it is simply a piece of carrion tied to the scabbard for show. As I wrote before, I have a "Naga" dao (really indistinquishable from a Kachin dao, and perhaps more accurately called that) which has a small piece of jaw tied to the scabbard. Mine is no tourist piece, and my strong assumption is that the jaw has a talismanic significance. I'll post pictures once I get home tonight.
I can't immediately remember whether a canine carries talismanic significance to the Kachin (or other hill tribe of Burma), so I'll have to dig a bit in my library. Its presence on my sword tells me that it is not a random thing, though.
On the other hand, I won't go so far as to say the whole sword is "legit" -- it is possible that the maker of this one added the jaw because it was something that is found on Kachin swords. The guard and wooden carving on the handle are not typical, so its probably a composite at best.
Why Kachin/Burmese? The straight, square-tipped blade is typically, almostly uniquely in the area, Kachin/No. Burmese. The open-faced scabbard is also typically (though
not uniquely) Kachin. Here are some examples:
It is described as being a Kachin weapon by Egerton, as well, though he calls it a "sword dao." You will also see the resemblance in the handles. The guard and the wooden fret-work are the odd-balls, but otherwise it is a very typical Kachin dha or "sword dao." Is there a similar weapon in Malaysia, by the way?
A couple more examples, but with closed scabbards which I suspect are a Shan (Tai) influence: