Time Lord Chronicles
TV listings for KTEH Channel 54 have a one-hour programme called "Time Lord Chronicles" showing as a late night filler after the regular episode of Doctor Who on 1 March 1998, 15 November 1998 and 13 June 1999 (this screening was from 1am to 2am).
Although it was said to be "A Mythmakers Production" by This Week in Doctor Who, this was not a known title from Reeltime Pictures who made the "Myth Makers" series of interview tapes.
While it's possible this was an alternative umbrella title given to a repeat or compilation of the Myth Makers editions for Jon Pertwee and Tom Baker that KTEH had already screened several times in 1997 and 1998 - see Airdates in San Jose (KTEH) - it's more than likely that This Week... was incorrect about the origin of this feature, and that it was actually an item assembled by KTEH.
(It's unlikely that this was KRMA's Once Upon a Time Lord, as the tapes for that early-1980s documentary were long-gone by 1998...)