Of course, this was based on the assumption that Thompson had made up the whole story and, having been caught, covered his tracks.
In hindsight, we now know that somebody was trying to peddle this story, though. So, Thompson would've had no apparent need to make it all up.
The possibility remains, though, that he might've been covering for somebody whose real identity he couldn't reveal for some reason. William McKinley, as I recall, tripped him up by convincingly establishing the fact that there was no such person as "Terrance J. Wilkinson".
If we take Thompson at his word, though, Terrance is "a CIA advisor". If he's not Wilson, that's still plausible -- Plame probably wasn't the only CIA-associated person in on this stunt.
Wonder whatever happened to Thompson. Wonder if he'd talk about this now...
It's quite possible Thompson made up a legend. In that case I'm at a loss for any leads, though, LOL. At this point my best suggestion is to check if there's any other information on counterintelligence agents who were approaching journalists and politicians in New Mexico around 1982. If that doesn't turn up anything I'm not sure where to look.