wrote

You really can't be sure about that "it isn't an FAA MEL". The MEL
policy/procedure has been in place and operating longer than the
"approved" MMEL program.

That should be fairly easy to research since an MEL constitutes
an STC to the aircraft, we just look in the aircraft documentation
for the STC, or better yet, look for the authorizing signature on
the MEL. I'm betting that you won't find one. :-)

Bob Moore