Actually I see you posted similar question in Stack Overflow
https://stackoverflow.com/questions/73255860/genero-42r-42m-files confirming that you no longer have the 4gl source code.
The question has been asked before in the forums, see
https://forum.4js.com/fjs_forum/index.php?topic=1376.0Short answer is No, but there are things you can do to help put something back together so that you are not starting from scratch.
Reuben