If you're the one who e-mailed that your subject was murdered by a second wife's first husband (or some such) you've probably been watching too much television. Since time immemorial men and women have disappeared for any number of reasons (it's a generally-accepted belief, however, that disappearances of the former usually involve the latter in one way or another . . . and vice-versa).
There's an old saying: "Act in haste; repent in leisure". During war - and in peacetime, as well - people marry the wrong person. Sometimes it works out, sometimes not. If he's alive, he knows exactly where he is and his concept of "lost" may not agree with yours. If deceased, it's probably from natural causes and the above still applies.
Alive or deceased, Social Security Administration may or may not have data on him for any number of reasons, pro and con (actually, SSA is a lousy source for tracing people anyway).
Send me his date of birth and Social Security Number and I'll see what I can do for you. If I incur any expenses I pass them along. If living, HE decides whether or not he wants to communicate with you - it's still a free country. I will, however, send you his address (or that of his designated NOK) and you can hash that out between (or among) yourselves.
With all the above understood and agreed, send me the requested info and I'll find him for you. You can post it or e-mail me direct.