[Animayhem]

I have noticed if you are under a certain level, the leader tends to resolve it alone. The caravan doors stay closed.

Nope it will resolve at any level. Now if you are a higher level more than likely the caravan driver or ships captain is fighting higher spawns.

In my experience, the caravan curtains stay open until fight is resolved.

Many wait for awhile and then assist the driver as by then usually the driver has the attackers almost at death's door.

As for the doors staying closed and fighting continues listen again to when the drover says that they are on the road again. The fight is over but the sounds of fighting still can be heard.