I don't know who to believe on that one. Even the Mexican's are saying what you just said; "if he was wearing a life-vest, where is he?" But I don't trust those bastards either.
That aside, there are some pretty bad hombres coming armed from that side of the lake. Who votes for USAF patrols with AGM-114's?
No way in hell I trust them either, but doing what I've been doing for the last 15 yrs, I have a pretty good read on people and their non-verbals. This young woman just watched her husband allegedly get shot in the head, she said she kept hearing God tell her she had to leave, they can't find the body, and all this in an interview within a few days of his death, as she kept looking down at the floor, in between what seemed like an effort to sob a little.
Typically if something this traumatic happens, and the "surviving" party is so willing to give an interview, or help in the search, they're trying to garner sympathy and compassion to help bolster their story, which in most cases, is a fabrication.
I'm not saying she's lying, I'm just saying I believe there's something more to this than she's letting on. Money? Another lover? Insurance?
Google the interview and tell me what you think about her actions/non-verbals.