I never post, but always read.
Robert was a healthy, largish man who went missing in daylight, in a populated area. His bike, and some work equipment seem to be missing with him. (??) His car was found at a railway station. Apparently the head of a happy family, we do know that there had been some problems in the past, with his wife's career change, and that, no matter what the family's income was, that they had reasonably high outgoings.
I don't know why the $300 was in the drawer, or the telephone, or why the car seat was forward. (Etc) However, it seems clear to me that the most likely scenario is Robert leaving under his own steam. For reasons that are not clear to us.
My father went out to work one day when I was six, leaving four children, a wife, mortgaged house. He had an ok-ish career. The next time I saw him was in a coffin, 33 years later. Another woman, another life. He was not a monster, just overwhelmed, and weak. He did have contact with his mother and siblings at some point after he left- I don't know how long after, because we had no contact with them. (Then) They have subsequently told us that my father said that having contact with us, (his kids), would cause us grief. He paid no child support etc, but, after about three years did divorce my mother, (via lawyers), and claimed his equity in the family house. (This was in the 70s, things are different now)
Sometimes people just take off. It is the easiest option for them, for whatever reason. I can't tell you what my father left behind in a drawer, or anything like that. He was gone. he was not there. He was nowhere to be found.