So in the List of what you can and can't post on this site, it says:
4. Upcycled customs: Any song posted by an author in the DB and reposted by another author with marginal edits. If you see a song in the DB that is missing an instrument or 2, contact the original author and contribute to that version. If the author is not willing to collaborate, start authoring the song from scratch if you want it released. If the author is unreachable or if you think there are special circumstances (like very very badly authoring of the original version from which you would start anyway to save time, for example), contact a moderator. If your edits are substantial (you are making a drums only song full band, for example), always contact the original author if the song is in the DB but in this case you can upcycle without permission for the benefit of the community: make sure the original author is properly credited. Upcycling without permission is stealing stats and recognition, which is what fuels the community of authors, and we can't allow that by any means.
For the case of Modest Mouse's Ocean Breathes Salty, the version in the database is drums-only. I had started work on my version after originally skimming through the database with a band-only filter. The rules state that I'm allowed to continue work on a song that has only one instrument, but I should contact the original author. But here's the thing: he hasn't been active in the community for about a half a year. I don't think contacting him will do any good. So should I just proceed with the authoring? Would I have to credit clumsy_plumsy as the original author even if didn't use their original chart as a basis for my own?