James Cameron has become tired of the preds that choose to die without honour by crouching against a rock or tree and self destructing.
This has been a thing since day one. The preds head goes inside the rock so you can’t kill him and defuse. It wouldn’t be so bad if a detonation wasn’t classed as an automatic win for the pred. This bug rewards failure.
If this is too much to fix by actually improving the physics then simply remove the need to shoot them from the front in order to kill them.
While you’re at it remove the effectiveness of the perk that strengthens the mask once the pred is downed. James Cameron has seen a mask take over a hundred point blank hits to remove it.
It has been written, now let it be done.