I’m pretty sure this issue is related and the answer there will help you: https://stackoverflow.com/a/15622021/7458681
tl;dr the cwd of the notebook server is always the base path where you started the server, no matter was running import os os.getcwd() says. Use import sys sys.path.append("/path/to/your/module/folder").
I ran it with some dummy modules in the same structure as you had specified, and before modifying sys.path it wouldn’t run and after it would