It sounds to me more like the guy went underground rather than that he's been arrested and disappeared into the system (or just "disappeared"). Lines from TFA like:

In the raid's aftermath, Meek has made himself scarce. None of his Siena Park neighbors with whom Rolling Stone spoke have seen him since, with his apartment appearing to be vacant.

"He fell off the face of the Earth," says one. "And people asked, but no one knew the answer."

and

An ABC representative tells Rolling Stone, "He resigned very abruptly and hasn't worked for us for months."

make me think he has chosen to disappear and that he maybe was informed that something he was working on had a high risk of coming back to bite him, both legally and perhaps as a potential threat to his life, especially since his new documentary project involves an incident between the military and ISIS, and the book he was working on involved things happening in Afghanistan as the Taliban took over. He has kids, and maybe he decided to disappear to protect his family. There doesn't seem to be any indication on the whereabouts of any of his family either.

If it was just a legal thing, he doesn't seem like the kind of person who would just keep quiet about it on this scale unless he knew he had royally farked up.