Mad Grey Dawn is an anagram for Edward Nygma. Just in case you guys didn't realize.

Okay. So Bill Evans. He was released 10 years after Kate. That means he and Beverly's meeting and planned escape + failed escape from Bill happened sometime between the 2 years before Ethan was released. Explains the decomposing body as well.

You're right. I didn't mean husband, I meant Bill. Who is Bill again? Beverly says she and Bill had a time and a place all figured out to escape and then one day he snapped and took off on his own.

Okay, I need to talk to people about this. I don't know anyone personally. Haven't read the books/staying away from spoilers. My theory is basically suspended animation.