Apologies for dragging this thread up again...
It seems it was XT859 that had it's tail end surgically removed by a bowser after all, and not XT864. I was talking to someone on a well known social media website about the incident and he apparently arrived on the scene in the immediate aftermath and witnessed the mangled tail in all it's glory, he also mentioned what I assume was the name of the bowser driver, but no need to mention his name here...
Anyway, here is a small image I've found of XT859 clearly showing the tail section missing up to the point where the stabs pivot, it's not too clear in it's original size, but when enlarged, it can be seen more clearly...
-RP