Hmmmmm... Let me make sure I am seeing it right. The pin knot runs all the way across the limb right? Is that gonna be the belly or the back? Looks to be two thirds of the way up the limb.
Not sure what I would do. What are your plans for backing? If I had a really clear and straight grained piece of hickory, I would draw it up so the knot was on the belly and see if most of it would go away with cut-out and tillering. Is the stave long enough to shift the bow down (maybe shorten it some too) to work the knot out the end?
Tough deal. After sitting in my thinking chair and agonizing over what to do, I would probably build it. If it blows, it blows.
I have had a few staves that just wouldn't work out. I cut them up for risers, handles and overlays.
Good luck with it. Let me know how it goes.
OkKeith