Why does Cathay's own website list the KLM lounge, and yet the lounge attendants claim Cathay ended their relationship with them over two years ago?...

Yes, CX strictly use the Plaza Premium Lounge from now on, which is a big upgrade from that KLM Crown Lounge. Not sure why CX never updated this on their website.

Both lounges are listed on CX web site . Since CX does not have own lounge, CX passengers will be directed to whichever CX designated lounge is. Are you flying 829 or 825?

829, in J. I got into plaza premium no problem, but was curious why Cathay listed KLM on their website, given they are Skyteam. I stopped by the KLM lounge to chat, and the attendant was very nice, saying Cathay had a deal with them up until 2.5 years ago. That's some crazy outdated information on the CX website...

Ok, question two: why won't BA follow the rules and let me into their lounge as a OW J passenger? Three different BA employees claimed I had to have OW status, even though the rules are very clear I'm supposed to be admitted based solely on my J cabin OW boarding pass. A quick web search led to numerous other examples of other CX passengers being denied entry and told they had to use Plaza Premium, going back multiple years. How have neither BA nor CX put a stop to this foolishness?

I am confused too, but I guess perhaps they may still be using the KLM lounge for 825, which is only three times a week. There can be two types of deals: (i) operate the lounge as a CX lounge, or (ii) simply use the lounge as a third party lounge.

BA has been picking on the wordings between lounge access by CoS and lounge access by status for a very long time. I thought that was over, but I guess still not:
* Tier status - Members of oneworld airline frequent flyer programmes with the equivalent of oneworld Emerald or Sapphire tier status can use lounges offered by oneworld airlines when departing on any flight marketed and operated by any oneworld member airline, regardless of cabin class being flown (exceptions are noted below).
* CoS - Customers flying First or Business Class have access to the equivalent class of lounge regardless of their frequent flyer status. First Class passengers may use a Business Class or frequent flyer lounge if a First Class lounge is not available.
I guess the term "equivalent class of lounge" is still up to the individual airlines to interpret.

FYI CX825 also uses the Plaza Premium lounge. ^

The PP lounge isn't stellar, but still very decent and definitely an upgrade from the KLM lounge.