Not the OP, but I am a fan of leaving breadcrumbs everywhere. That is, every bit of documentation should point to other bits of documentation. Code comments point to the corporate wiki and vice versa, commit messages point to issues, issues refer to commit hashes, log messages might say who wrote a service, bespoke server and container images could have a README in /, internal DNS can have text records, etc.
We have to accept that we will sometimes play digital archaeologist. That's a good thing! It means that the technology we're studying was successful. So given that, it's better to have out of date documentation than zero documentation, so that we can pick up the trail somewhere.