I agree with that, but some people consider weapons with spirit to be healing gear. I'm not arguing this point, just stating a fact. Since he didn't get a confirmation he shouldn't have assumed that this particular raid leader didn't have this opinion. I think OP was blinded by wanting the staff and ignored quite a few warning signs that made it quite clear he wouldn't get it. Wishful thinking is a dangerous thing.
Of course, he can try to ticket the GM, it could go both ways. But ultimately, I think the whole issue was avoidable to begin with. Just don't join groups that have no idea about how good spirit weapons are for hybrid casters.