I have created an aggregator that scraps the external resources from anidb and places them in the following json objects. You could use this to make a better matcher than the one you currently use which requires manually entries in github, as this uses the direct entries from anidb.

See:

* https://github.com/notseteve/AnimeAggregations/blob/main/aggregate/TmdbToAniDb.json

* https://github.com/notseteve/AnimeAggregations/blob/main/aggregate/AnimeToExternal.json

If there are other external links you'd like me to add, such as TVDB, feel free to open a feature request on that git repo.