[crazygringo]

No, the message history wouldn't.

Because the message history was for his actual account, not the criminal's account.

The whole point is that they looked up the wrong username. And when they looked it up, they found an innocent man's identity, but didn't bother to look at the message history, which would not have had any of the messages.

Which is super-weird, because if he'd been messaging this one child, you'd think they'd be looking at all of his messages to find potential messages with other children. And then immediately noticing the lack of the messages that started the investigation in the first place.