That stave you have pictured is swiss cheese, toast, fubar, gone, in other words it's firewood. I've seen that before and unless you want a bow that looks like it's been shot with buckshot when it's done, I'd pick another one.
Check all the rest of them because they may not have gotten into all of it......yet.
You won't know till you get all the bark and sapwood off them, and I'd suggest you do it right away.