[James2001]

Did the Thames name ever truly disappear though? I do remember the late 1990s logo with “Thames - A Pearson Television Company” with the once proud logo reduced to just Tower Bridge, but was there any period when it was just Pearson TV, with no sign of Thames? If there was I think it may have been very brief.

No, it never disappeared entirely, but Pearson did use several brand names in the late 90s/early 00s (Grundy and Fremantle most notably) and they did seem to start getting more prominent at the expense of Thames before the end, then in 2001 they got rid of the other names, in the UK at least, and used the Thames name exclusively.