After reading through this thread, it seems pretty unlikely. What is his motive, and why in this way? On the other hand this really smells suspicious.
It sounds like a "hit".
The case underscores the risks U.S. agents face when they work with shadowy informants who often come with criminal resumes, U.S. law enforcement officials said.
As an aside from this story, there is zero sense in the policy which allows federal agents to use the most "shadowy informants" and methods in crime work but the CIA, working only in foreign countries, can only recruit Boy Scouts in their undercover work.
Usually people don't decide to commit suicide while on their way to some conference. It doesn't sound like he was despondant in any way.
You familiar with Operation Canton Song in Panama and the Justice Department's De Feo report on DEA plans to assassinate Panamanianian Head of State Omar Torrijos and customs department head Manuel *Noryago*? Before the canal treaties were signed...?
That one cost a DEA Administrator his job...