Was it only on paper or did you get it digitally? If the latter, zbar should do the trick to decode it. If it requires iOS or Android, that'd be a cue to info

Was it only on paper or did you get it digitally? If the latter, zbar should do the trick to decode it. If it requires iOS or Android, that'd be a cue to inform them how you currently don't own a device with either and ask how to make it work on your Pinephone running Mobian. More people need to be comfortable with being uncomfortable for this to start changing. Assuming employees will have personal Android/iOS devices and require registering and using them for work functions is something which needs to be mentioned in an employment contract to have any standing.