The Mail's photo has several redaction marks but, further down the article, they quote from The Mirror and one identity is unredacted
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He said: 'As we expected, he has issued a flat denial. For my part, I must accept the situation, although I would be less than fair if I were not to record that his [Blackburn's] recollection does not agree with the first thoughts of his agent.'
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The article sets out the context of this wording (ie TB's 'recollection') as his response to questioning about his movements on a specific night, detailed in her diary. You will note that the memo doesn't state that explicitly, so where they got this idea is not fully apparent. It's like sleight of hand: keep your eyes on the memo while they insert the idea that he faced questioning about his movements.
If I was innocent, I think questioning of that ilk would stick in my craw and still not be forgotten, 40 years later.
So… what's this about his agent, supposedly knowing his movements, on the night. Also, "thoughts"? Sounds like the agent was asked but, at best, could only guess. Hence, don't read too much into this. I'm only pointing out that someone *outside* the BBC was aware a disciplinary incident was in progress but didn't take it further. After all, what agent would want to undermine their own income stream?