Update...
II had a nice, long discussion with my FIL this past Sunday afternoon. I started by asking him to read the article posted on here. He actually did read the whole article. When he finished, he nodded and said something to the effect of "I get it". I explained to him that the family, and especially his daughters, are past worrying to the point of preparing themselves to get a call from the State Department. He insists that he is not going into this thing with "starts in his eyes". I told him that I disagreed.
He told me that he has been communicating with her for about 9 months now. I really think that's the issue, He's so far into this that he is insistent on seeing it through. He didn't bat an eye when I told him he may be parted with $20,000+ to "see it through". A cheap roundtrip ticket is about $2,000. He realizes that and said that if things got sideways, he'd head for the airport.
I did mange to agree to some safety measures: trip insurance, a phone call to the State Department to let them know where he will be, a cell phone with an international package and a hold on his bank accounts that only his daughters have access to.
If everything goes as planned, he will be leaving mid-July. I'll keep posting.