yeah 1.12.8 is the same Version that I have, You use a modpack don't you?
Sort of. I built my own private modpack for my friends and I to play around with; it's not based on an existing modpack or anything, I just grab the mods from curse and configure them to my liking.
Maybe Gany's Surface automatically disables redundancies if Gany's Wood Stuff is installed alongside it? There's an option in the Gany's Surface config that enables these chests:
The only other thing I could think of is maybe the .jar I downloaded was deleted and re-uploaded at a later date, but that's unlikely.
Here's the MD5/SHA1/SHA256 hashes of the jar I have (note that the MD5 matches the one listed on curse):