Thank you for the correction, I'm not so familiar with the am/pm clock.
Nitpickingly, WGT has two clocks, plus a variable one.
You reference their CDP clock, corresponding to GMT and displayed on the game's home screen (PC).
Tournament and forum clock is what I'd consider "WGT clock", their home time zone from San Francisco, PST or PDT respectively.
Add the CC clocks, individual to each CC and used for their CC tournaments. They correspond to the CC's "home time zone". The origin is undisclosed, maybe taken from the first owner's nationality. My CC is "German", time zone is CET or CEST.