Maybe try to have an extra feature in the game in which you can put a self destruct on individual tanks that come out, that way if a tank does get stuck you can simply remove it if it never finds its way back to the recycling department.
all you need do in that case is to have one of your other tanks / vtols target the offending tank. blow it up real good.
you will loose it and it will be out of its misery.
I didn't think you could do that though thanks for the info