No need for that, if you ever need to develop & use that backup you’d just read them right off from the negatives

Also when crossing borders you could have it unspooled inside of the film canister (done previously in the dark ofc), then if some fiat goon wants to inspect it all it’s gone the moment it is opened!

This totally works if it is for backup ONLY, all you need is an old camera and film. Hell, even coffee can be used as developer hahaha