I guess it's splitting hairs, but it seems to me that there are at least four distinct categories
1) a prop made for the production that never made it to a set or filming location
2) a prop made for the production that made it to the set or filming location but didn't end up on film (a duplicate that stayed on the rack, or was set-dressing on a set or part of a set that wasn't filmed, and many other possibilities)
3) a prop made for the production and ended up on film but was in a shot or scene that didn't end up in any of the cuts which were released (initial theatre run, Director's Cut, "making of" video etc.)
4) a prop made for the production that ended up on film in the final cut of the film as it was released in theatres or in a later Director's Cut, "making of" video etc.
I'm guessing that props in the first category wouldn't be labelled "used in production".
I'm guessing that props in categories 2, 3, and 4 would be labelled "used in production" though only props in category 4 have the potential for being "screen matched". So "screen matched" appears an effective way of weeding out everything that isn't in category 4 including fakes.
Then of course there are props that don't appear in the film but do appear in publicity stills or production stills. Are stills considered "screen"?