Help? Lost item at North site 9/28

Hey all-

Just got a call from my shooting buddy. We hit the North spot on Sunday 9/28, much lead was spent and fun was had. Somehow he apparently lost his rear Troy BUIS off his rifle, and swears the gun hasn't been out of the case since then... until today, when he noticed it was missing. He also swears he had it on about as tight as he could get it...
[Dunno]

We both realize it's almost certainly gone/lost forever, but he asked if I would post here just in case one of us happened to find it. If anyone here miraculously found it, or happens to hear of such a discovery, please respond in this thread or PM me.

Thanks!