It's true iff you haven't made any effort to find evidence whatsoever OR there's a zero percent chance that you would find evidence even if it existed. This is a very rare circumstance, and one that doesn't apply in this case.
There were some logs that. had there been exploitation, had a non-zero change of providing evidence of said exploitation.
They looked in the logs, and there's a non-zero chance that, if that evidence were in those logs, they would have seen it.
P(exploitation) < P(exploitation|they had and looked at the logs)
It's true iff you haven't made any effort to find evidence whatsoever OR there's a zero percent chance that you would find evidence even if it existed. This is a very rare circumstance, and one that doesn't apply in this case.
There were some logs that. had there been exploitation, had a non-zero change of providing evidence of said exploitation. They looked in the logs, and there's a non-zero chance that, if that evidence were in those logs, they would have seen it.
P(exploitation) < P(exploitation|they had and looked at the logs)
That's the definition of evidence.