I still have nightmares of modifying old indicator infested RPG II spaghetti code for a local hospital to create magnetic tape versions of UB52 and form 1500’s.
I don't know if I would remember enough to be able to read an RPG program nor would I recognize RPG III and newer. We did use a third-party app that gave us RPG 2.5 where I worked last doing RPG. I still have 8" floppy disks with utilities I wrote at the time and the Pop editor.