It is hard to tell when you are quoting from wikipedia and when your own commentary begins and ends as it is all mixed in together. Most of what I stated was from my own research long ago and conversations with Poke Runyon when he was annotating the Cipher Manuscript.
Are you saying that the Tarot correspondences and links to the grades came from the 18th century German order rather than from MacKenzie? If so, do you have any direct evidence of this? I believe we are talking about the Tarot sources here and what Pixie would have known or not known.
I haven't seen 'direct evidence' , above is listed some of the info about it, people can come to their own conclusions, I see it as not impossible that it came through MacKenzie. MacKenzie knew Levi . <shrug> I cant be positive and undoubting about it (and I dont think anyone else has been or can be ) .
Indeed there ARE gaps , as you state; " The piece still missing is any demonstration that Pixie was a Tarot reader and astrologer - that she knew the Tarot history and lore (not to mention occult, astrological and Masonic symbolism) separate from Waite. "
The issue seems to be that there is not ANY demonstration (yet , that I can see) that Pixie knew "occult, astrological and Masonic symbolism " separate from Waite ... my ASSUMPTION is that he communicated it to her.
There seems to be some confusion around 'designed by' and 'designed totally by herself with no input from Waite', there may be no record of this, not that this indicates it cant have happened. There seems some resultant postulations;
* Waite did give Pixie some info to help her design the minor cards, but we have no evidence of it.
* Pixie 'intuited' it as she is said to have done with others.
* The occult, astrological and Masonic symbolism isn't actually in the minors, its a form of 'pareidolia' .