I know this is old, and this issue still exists, and it is EXTREMELY frustrating.
Here is your workaround. Zoom out. Continue zooming out until only listings that aren't "missing: xxx" are included.
It appears that when you are too zoomed in, and there are too few results, AirBnB includes listings that you want excluded. This is poor UX. It is an effort to garner more purchases, and I am sure that their data support this practice as users may decide, "well maybe a hot tub isn't REQUIRED" and select a listing without one.
In my opinion, there should instead be a small notification on the bottom of the map if there are no listings that match the filter. The notification should say click here to see 5 listings without xxx or something. Or your filter is excluding these listings. Something else besides this practice.
It is beyond frustrating that their filters do not work as filters are universally accepted to work.