Actually, I believe that the slavers do not know who we are or what we look like; if they had seen us, they would have singled out whomever they thought to be the leader and pulled him aside privately instead of asking for two representatives so vaguely. I also think that if they knew who we were, they would not have been so willing to meet us, they would have taken much more cautious measures.
I do still think that Hissra's plan is more sound, however; it may not be the easiest to pull off, but I think it ensures the most safety for everyone.