If you want to have a check wether the person has been talked to just use in-game resources.
k_con_talkedto checks if you've talked to a person, and k_act_talktrue makes it so that the game recognizes that you've talked to the person, basically this:
Code:
void main () {
SetLocalBoolean(HAS_TALKED,0,TRUE);
}
Anyway, I use that a lot in KotOR 1, I don't know if it works in KotOR 2.