First post, but ill cut right to the chase:

Bug:
If the person that rolls the team mission leaves and gives another leader ship and the item that you need to deliver somewhere, then leaves it will not be possible to complete the quest. No one bot the roller can use the mission item on the mission .. "machine"...

Solution:
Everyone in a team can use mission item on mission machine
or
Some wierd bug in the last 2 mission i played that only affected that team