We agreed I'll reach out to him when the issue is resolved. He's still a member!That's unfortunate...
I've been making decent progress with the security company. It's technical. Both Xenforo and Securi (our security company) are working on it. Something to do with caching, and how Xenforo formats headers.
Caching is totally off right now. So if THAT theory is correct, it's fixed NOW.
Please let me know if you see any issues.