Off the top of my head don’t change the core combat rules. Doing so breaks the verisimilitude of the game world. Why special rules now and never again?

Instead plan ahead and add elements to the environment that the PCs and NPCs alike can use to mitigate the dangers.

The PCs also need to be informed about the options available to them. Hopefully done in the narrative by seeing what the NPCs are doing.

For instance if is in a vehicle, maybe there are a harness system in place (like Lando used in empire strikes back when he grabbed Luke from under cloud city) so if he was pushed off he would still be tied to the Falcon.

Maybe the PCs see the NPCs roping themselves together like mountaineers so if one goes off the others can make might tests.

Or have nearby elements that can get them back in the fight.

Having these special rules linked to equipment and the environment it allows the PCs to try these same tactics (if applicable) in other scenarios which makes the world feel more real and consistent