With Jamba, you have it on each account, and put all of your toons into the same team.
Basically pick an initial leader toon, and add each of your slave toons to the leader's Jamba.
And have the initial toon as the leader on this account.

Then switch to each other account, and add only the leader to the secondary accounts.
On the secondary accounts choose the initial account toon as the master toon.

Once this is done, go to the master account and select "Push Settings to other Characters".
Now they should all have the same settings and the full team.

So you can make changes to any of them, and then push the settings across.

For a quest person, you would target the quest npc.
Hit your assist key so the slaves have the npc targeted.
Ideally have Click to Move enabled on all the slaves (interface - mouse options).
And have an Interact With Target keybind (keybindings - targeting functions).
And the slaves would run up to the npc and interact with it.

Any option you pick with the main, the others should copy.
With the exception of quest rewards, which follow the quest settings you have in Jamba.
Everyone do the same, everyone pick their own reward etc.

Khatovar has a post/guide to Jamba.
Pretty sure its a sticky post in one of the forums.