Well, since he said nothing about it possibly getting back up, you could always take the death animations frames, say they were 200-210, knowing that him on the ground would be frame 210. Then change the idle frames(or maybe the spawn frames and delete all the rest?) to be "210,210" in the fpe, and use the coward scrip or something similar where they never attacked you. If you wanted it to take no damage, redoing the main script or even the addition of "col= off" may help. Maybe making the character indestructible.
Now this isn't a tested method and I have no use for this myself so I'm not taking the time to figure it out, but you can get the idea and perhaps build on this base and these theories to accomplish this task with no modeling application what-so-ever.
Good luck
Loc