Perhaps you can create a corpse item/unit (with a corpse or wounded man's model) at the unit's 'death' and remove the unit from the game permanently. The stretcher can carry ONE item no problemo (copy and paste Hero Inventory and then rename it, reduce the inventory of 6 to 1, and then turn "Hero Ability" to false instead of true). As for requiring two units to move, I'd have to think about that.
...Perhaps it should have a cargo hold (copied and pasted and changed to hold 2) that "requires" two people "inside" the stretcher to make it move. I'd have to think about how the condition would go, though.
(Number of units in (Units within 512.00 of (Position of (Triggering unit)))) Equal to 2
This is the best I can do, but then you can't load your units but rather move them near the stretcher to keep it moving. And at the moment, you can move your stretcher even if an enemy comes. So basically, you'll end up having kind enemy soldiers allowing you to tug your stretcher along some.
