So you went camping with a guy named Bob but his name is Kenneth, basically because the people who introduced you didn't actually know Ken and they introduced him as Bob. And as hard to believe as their ignorance is, they even put down everyone else who wasn't acquainted with Bob, but Ken hasn't let on to them about the whole thing. Mmmm.
Anyway, because your friends, you started camping with Ken who you've been calling Bob. Well, I suppose if his name's not actually Bob, maybe you could politely ask sometime if it's OK to be calling him Bob.
Bang