Andy, You've lost me. Copyright relates to the protection of original and inventive works. I don't know W.R. Chorley's "Bomber Command Losses" series of books but it can only be a compilation of Bomber Command records provided to Chorley by the RAF. I don't see Chorley as the original source or author, he invented nothing.
I'm baffled. Chorley is claiming no less then the exclusive right to compile lists of Bomber Command losses. Make sense? If Chorley has, as you suggest, caused the loss of the web site through a copyright claim then someone needs a 'serious talking to'.