Aw yes, the hellscape that will exist when someone's pet micro-service losses it's creator as they leave for another org. They decided to write it in a language that nobody else on the team is familiar with, and now that decision has come home to roost.

Additionally limiting people to only writing own micro-services if all the platform guarantees (guard rails, really) are implemented is a good idea.

If the platform-standard tooling still works -- expected logging libs, tracing, etc -- you can use what you like to do the actual work.