What happens to incapacitated soldiers?

From personal experience of being a bit sick in the head and playing a good bit of Sniper Elite V2. When you incapacitate an enemy on the battlefield and allow his buddy to pick him up, the "still standing" enemy will bring the wounded soldier to the sides of the battlefield out of the way and set him down, then return to the battlefield. After you kill him you can go to the wounded enemy who may or may not still be alive. They can bleed out if they have been moved, or they could still be alive. I have not personally seen one get bandaged up and return to the battle. There is a chance that they could de-spawn as a result of being "saved" but I do not know that for sure either. I hope this helps!