Developments
The player can alter the mood of the quest throughout based on how active they are on certain cues. They may heighten suspicions if they overhear the conspiracy and tell others of the plot to ruin the journey. If they do nothing to quell the paranoia that amounts from the discovery of the balm, the suspect is apt to be killed and thus undermining the morale of the group.
This is further emphasized in how suspicion may overtake even the players as the trail gets more treacherous. If players are generally very passive and nonchalant, they may be subjects of suspicion or snobbery. The players should actively try to be defending the fragile pilgrims lest they fail their job or look undeserving of the end reward.
Also, if the players take part in heightening the tensions and paranoia, that may hinder the pilgrim trail to take more breaks and so prolong the journey. Players can also interact with NPCs to possibly discover some of their resentments toward the pilgrims or scratch the surface of some dark secret, particularly those who may hint at their future betrayal. If the player succeeds in interacting with the person well enough, they may be dissuaded from becoming a true enemy later on.
Treasure
The players get the most goodies by seeing the adventure to the end and successfully escorting the pilgrims. Of course, they are free to search the bodies of the fallen. Among the bodies of the conspirators, in particular, should be some explanation of their intentions, perhaps a letter. There shouldn’t be too many special things to find from the mob’s corpses.
If you desire some sort of distraction, the nest of the goblins can be planted somewhere, filled with some small stash of arrows and some coins. This can, however, be a decoy to lure adventurers’ attention whilst some enemies attack the pilgrims. In the end, the pilgrims may bestow the players with rewards for their troubles, granted most of the escortees made it in one piece.
Conclusion
At the end of the journey, you will probably have finished escorting the pilgrims to their destination. By this point, they convene at the place of worship with some of the keepers of the sacred grounds and procure some item that will substitute for the sibyl’s balm and the pilgrims will be inclined to release the players from their service.
They will give rewards, depending on the DM, along with a religious favor of their denomination. If the intentions of the conspirators were not revealed, the pilgrims may wonder but not dwell so much. They may ask the players to stay the night or offer to have them rest for no charge in a nearby town or some resting quarters with food and drink. Afterward, the players are free to leave and continue on with the campaign.