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I can't help with that specific quest but in general an escort quest will pop up an accept/decline for all party members and I might be wrong about this as well but Jamba could be auto accepting those accept/decline prompts. So in your last scenario you didn't see the accept/decline box because it was auto accepted.

In the 1st instance you might have encountered a problem because you had the quest dialog open already and maybe the accept/decline prompt didn't come through to the clones. I didn't have a problem with this when I did the escort in RFD yesterday though. I popped the quest open on everyone via interact and Jamba is set to follow leader on quest accept and all my alts got the quest and completed it 1st time.