The Tischer parts manager is right. The part number of the FILTER is 11427788461 the part number of the kit w/ the filter, etc is 11427788460. And the proof has been in the OP all this time
Look at the picture of the old and new filters side by side. It's hard to read yellow on white but the part number on both filters is 11427788461. BTW the part number on the new filter is upside down. The last few digits are closest to the camera.
Funf Dreisig