Good enough? I mean it’s allowed. But it’s only good enough if a licensee decides your their goal is to make using the code they changed or added as hard as possible.
Usually, the code was obtained through a VCS like GitHub or Gitlab and could easily be re-contributed with comments and documentation in an easy-to-process manner (like a merge or pull request). I’d argue not completing the loop the same way the code was obtained is hostile. A code equivalent of taking the time (or not) to put their shopping carts in the designated spots.
Imagine the owner (original source code) making the source code available only via zip file, with no code comments or READMEs or developer documentation. When the tables are turned - very few would actually use the product or software.
It’s a spirit vs. letter of the law thing. Unfortunately we don’t exist in a social construct that rewards good faith actors over bad ones at the moment.
If it’s a backup server why not build a system around an CPU with an integrated GPU? Some of the APUs from AMD aren’t half bad.
Particularly if it’s just your backup… and you can live without games/video/acceleration while you repair your primary?