Well, Fredar is about suggest that we leave a hostage (possibly him) with the gobbos as surety until the shaman gets back from town. If that or something else doesn't work to convince her to go to town, Fredar will push to go on the search.
While Cromwell might be a logical choice, I'm not sure he'd be good as an NPC because it would be Fredar's tendency to alternately defer to his leadership and rebel against his authority- both of which puts pressure for party decisions on the DM instead of players.
I'm thinking maybe Hadarook for his scouting and outdoor skills?