Like a few of you, I don't believe he walked out on his family, specifically the kids. We can all have various opinions of IM and their relationship but no one has said anything about him being a bad father. In fact, no one has come out to say anything bad about RM at all. This is pretty rare.. He seems like a solid, good guy.
I feel this is foul play, for sure. I just can't seem to find a good, gut feeling about the why's, who's, etc.
Money doesn't seem to be a motive at this point - unless this has something to do with the copper. Even that though, doesn't seem to be my focal point. Because his body wasn't found, I wonder who has hidden him and why. (assuming he is no longer with us)
Street type criminals would not hide his body and stage his car the way it was found. This was something organized on some level.
Not pointing fingers but some thoughts in my head today:
drugs
gambling
$ owed
marital affairs
Greed, love, lust, & money. I am being hypothetical here and am not saying that this is the case but hey, we just never know. Maybe RM had an affair or a fling and the spouse of the other party found out. Doubtful but there are so many options here..
I too hope he is alive and returns home but the more time that passes, I don't feel he will.