If we see more cases like this one of someone disappearing without a trace and their disappearance getting documented but not explained, I'll accept this one as evidence to fuel future speculation. Until then, speculation used to fuel speculation is a dangerous path.
EDIT: Apparently my reference to conspiracy theories is pushing buttons? Unfortunately this is literally true: the logic of the conspiracy theorist builds upon itself, with as minimal reference to exterior circumstances as possible. The lizard people did it. How do we know? Because they did it before!
If we want to be different from conspiracy theorists, we need to cultivate an insistence on reasoning from documented facts, rather than building elaborate towers out of theories alone.