Can load the datpack on the world save file and the server, cannot find the resource pack in my settings, even though it is in the folder.
I can see the names of discs and i noticed creepers drop the discs when killed by skeletons, but the textures (custom disc designs) do not load, instead i see only default Disc 11 textures and no music comes from the jukebox when disc placed inside.

It seems like something is wrong with your resourcepack. Did you zip it yourself or did you check the "generate pack as zip" when you created the resourcepack? Are you able to upload the resourcepack so I can take a look?