I agree with rax that if Elsa doesn't want the others to go ahead with other plans before trying to negotiate, she needs to make it clear how she means to negotiate - either by telling them the plan or showing it in practice. The last thing she said for them to go on was "we've nothing to bargain with, do we?" - I think you can take it at this point that if any of the other PCs had any ideas to contribute there they would have spoken up.

Meanwhile, just an IC reminder - this is a tense, dangerous situation with a lot of noise and a lot of potentially dangerous goblins not very far away from your PCs. Even if it's not the plan you'd personally prefer, choosing a plan to follow as a team is probably better than convening the committee for plan discussion on the ravine's edge.