You do have a point. Just the same, first off, most murderers are 'novice', for better or worse, so I'm not sure how valuable the distinction is. Second, (*and this is under some assumptions about what might have taken place*) not all novice murderers (or murders, full stop) have the ease of an elderly, trusting victim, private in a residence. Again, speaking hypothetically, if the murderer knew the victim's habits (perhaps was even coached on them by another party), and had (as may be the case, given the wonky timeline) hours to sort out the details, I wouldn't think it too hard to collect a couple items that the victim was known to take with him out of the house.
It may be argued that someone who is responsible for and would profit from a victim's death (beyond that of a disappearance) might want the victim's body to be discovered immediately. While this is true, I would imagine the party responsible would also hope not to be tied to the putative crime, and might hope that LE would stagger in their investigation. In that event, the best possible solution for that would be to have a missing person who is presumed dead for legal/estate purposes.
Again, not pointing fingers -- just looking at how the field of possibilities, means, motives, and opportunities could play out. (And still curious if family has offered a reward.)
