I got the feeling later on in the event that the orc patrol that stopped us earlier had been the cultists in disguise. But there were only 5 of them so I dunno.
But I'm inclined to agree with Gergel overall in this instance. Though I've not been along for most of the times we've encountered Joe (last time I was there to see Joe was in Icecrown I think :P), so I can't really comment much on him specifically.