I would suspect they have a conversion facility in china perhaps that is packaging the stuff in various formats slitting down from bulk rolls.
I know that Lomography had been using Agfa aviphot negative in their CN films in 110 format and 120 etc.
Lomography has repackaged from the following brands:
Color reversal: Agfa Aviphot 200
Color negative:
Ferrania and Kodak, speeds 100,400,800.
B&W: Foma Fomapan 100, Kodak Tmax 400, and i think another film from Kodak or Foma.
"Purple" C41 film was supposedly made by Adox and/or Inoviscoat.
Most of these films had the same backing paper in 120 format, so the conversion seems to have been done by the same company, not by the film manufacturers. As you say, probably in China, however the boxes said other countries, not only china: "Made in the EU", "Made in Italy", "Made in Belgium"(or was it Germany?)
Since they have sourced from so many companies, i doubt they would see any problem in doing the 126 deal with Ferrania.