The number overlap b/w Foma and Ferrania occurs with their Fomapan b/w films...but Foma might have (wrongly) reused the cassette for their b/w films too.

The emulsion number should be the same for original and OEM/rebranded films as that's an IEEE assigned number and there are a number of patents around automatic processing based on the emulsion (one is Kodak's). That's what the DX number is for (which is a human readable translation of the barcode that can be found on the cassette which is read by the automatic processors).