A logical inference comes into play when there is sufficient evidence to justify a logical inference. Such is the case here.
Rejecting this logical inference (in the absence of any counter-explanations of your own) is tantamount to saying 'I refuse to accept the claim of a cover-up because you cannot provide the kind of full documentary record that would have been available had there not been a cover-up'. It's a heads-I-win-tails-you-lose style of argument more usually associated with cornered LNers.
It's a heads-I-win-tails-you-lose style of argument more usually associated with cornered LNers.You may not understand or accept this, but your "logic inference" strategy is commonly used by "I am right unless you can prove me wrong" LNs.
And FWIW, the large number of anomalies in the available evidence, including the one we are discussing here, makes it IMO highy likely that there was indeed a cover up. It remains to be seen, however, what the nature of that cover up was.