I belive that the 20k, 520ohms indicates a range of readings possible, depending on the setting of the horizontal size control... 2.2k is within that range.
As far as the high voltage on the plates of the vertical output tube is concerned, my guess is that your under voltage rated caps may be leaking CRT deflection high voltage back to the output tube (6SL7).
Until you replace the mis-matched under-voltage caps that you have in the vertical output circuit, all bets are off.
jr