Alternate option, get on the floor and look across where it probably is.

That’s how I usually find it.

Apparently if you are smart or clean regularly, you can just like… go buy some pantyhose for a dollar, and put a leg over the vacuum tube and just suck all the shit into it, typically including any screws. If you don’t clean regularly, you’ll be disgusted, but you’ll probably find the dumb screw.

As a bonus if you really wanna be lazy, you can put the hoes in the tube somewhere upstream of the main intake, so you can vacuum as normal and still catch the thing you lost.