I have been reading for several hours now, just trying to catch up...
My own feelings are that the father is not involved in this. I just feel he's too raw, too forthright about everything, even if it could get him in trouble. I appreciate his candor and after reading everything, feel like he's tried to be a decent dad under rough circumstances.
As far as MC, I just don't know. I'm beginning to feel like it's increasingly possible that she was not home when Haleigh was taken, that she was off at her brother's or somewhere, visiting, even smoking pot, who knows? When she got home, she realized what had happened and made up a cover. She's now too afraid to tell the truth.
This information about the A/C man is very disturbing to me, I've been fixated on him or whomever was over at the house with the brother that day, his "friends". This A/C man makes sense though because if it was an hour haul for a regular guy to come to that area, the owner would have wanted to do things as cheap as possible, what better way than with a relative. He may have left the deadbolt unlocked, then came back later to spy. He got lucky when MC went out and wasn't worried at that point about leaving a light on.
My concern is about him and any of these 44 SO's. Although we've heard that they were talked to and their homes searched, I don't think that ends things. Sadly, if Haleigh is dead, they may have stolen her, killed her, dumped her, etc... all in a few hours. I'm sure many of their alibis amounted to being home alone in bed, it was a weeknight. Who knows?