You can't copyright facts
"using copyright data from Hex's manuals"
From the *manuals*, not the source code. AFAICT WYP have done no more than made use of a collection of factual information, albeit gathered and supplied by a third-party. Unless WYP were republishing the tables from the Hex manual themselves, I don't see how it's copyright infringement.
FTS could have claimed "Trade Secrets", which seems like it would be more appropriate in this case, but only if WYP (and their other customers) had been made to sign something acknowledging such.