He wouldn't even need to be abducted. All he would need to do is get drunk enough to talk about confidential security matters and not notice that there were people in earshot who may relay the info to hostiles.
I'm not in a profession even close to the sensitivity of Presidential Detail, but even I would never have gotten falling down drunk on a business trip with co-workers. It's just totally unprofessional.
I was just giving multiple scenarios of what could happened in regards to some SS agent falling down drunk...Obviously there are many others.