Paul,
That's a real tough one!.
I've been put in this situation a few times and I can't say that I enjoy it, at all.
My advice would be, if you are going to do a report, be absolutely impartial.
Just concentrate on the work that needs to be done to bring the installation back up to Regulation standard, that's the most important thing here!. [Linked Image]
What happens after you have done your report, is entirely up to the two parties in the argument.