And can’t replace it b/c they’re on “National backorder” what can I do legally? Haven’t found a salvage yard that can sell one to me either

 

Improvise. Best you can do under the circumstances. Going the legal route is only going to cost you money, and accomplish nothing. Parts will likely be in by the time you even get a court date.

 

from what they’ve told me, there’s no way for them to order the part rn. It’s on national back order. I don’t know how to improvise with that. I’m driving around without a cabin air filter cover currently. What damage will that do? I have babies and don’t need to be driving around with filthy air. I’ve already been sick from this a few times. It’s disgusting and makes my skin breakout

 

Where do you live that the air is that bad? Air filters in cars are a relatively recent development. Like, the last few years or so. (on 'average person' cars at any rate. I am sure Bentley, Rolls Royce, et. al, have had them for over a century.....)

Put the filter in, and duct tape it.

 

Okay so the cabin filter is under the cowl of the windshield. Get a small piece plastic and duct tape and cover the filter. Or the cover you are talking about is part of the cowl?

 

Is it the flip top cover where you slide the filter in or did they smash the actual housing that holds it? Picture is worth a 1000 words. Almost a guarantee you've spent a good chunk of time in a vehicle that didn't have one lol.