To complete the mission you only need to rescue a certain amount of
 people, but if you wait to long some of the people in the hut will
 die of old age or missing food and the you can't complete the mission.

 The fastest way to do it is:

 1) Ask all the people of the hut to get out, then select them all as a
   group..
 2) Have them walk to southwest-corner of your land around the hut, see
   that border-line going north-south ??
 3) Have the people walk on the western side of the border all the way
   down to your main land, then ask them to enter the HQ (By RMB on the
   door) and you're done :-))

 (That worked for me, you might have to walk on the eastern side of the
 border, or even ON the border to avoid attacks. Keep your people walking
 by clicking in front of them, if they reaches your last click they'll
 stop and spread out, most likely crossing the border and alerting the
 enemy..)
+++++
if you send your soldiers up to meet your men then they can protect them.