I would need to know how fatal they thought it would be. It's an odds game. Things that get tested on humans are usually pretty safe though for the most part or it would have not gotten to that phase yet so I would do it.
No. It would most likely be a shady deal. They would never have gotten the official O.K. to test a potentially fatal drug on humans, thus they must be acting illegally. Who knows what that drug might be...
But even if it was official, I wouldn't. I wouldn't for any amount of money.