Tradition's Toll Quest - Cannot Complete

I know I messed up as I finished up Act 2 (Cruel) and in a hurry I went ahead and progressed the storyline into Act 3 (Cruel) and immediately noticed I still had the Final Letter in my inventory you pick up in Deshar and are supposed to ask around the caravan about said letter until eventually the NPC Shambrin takes it off your hands and you receive the book of specialization. Unfortunately now that I've progressed into the third act and upon returning to the caravan I notice no NPC on the caravan has the option for me to bring up the letter and now I cannot get rid of it from my inventory nor receive the passive points for the quest. Is there any quick fix to help me out with this issue?

So, apparently when you're in Act 3 cruel and you ask the horned lady to take you back to the caravan you'd expect to end up back in Act 2 cruel but, no, I was constantly being taken back to Act 2 normal. After going to Act 2 cruel specifically via the waypoint I was able to complete the quest so apologies for the confusion on my end!