As I guess you saw in the other thread, the Beta editor is limited, at this point, in its handling of shared tables. So (I’m just guessing) it’s probably better to focus on what’s going on in the Classic editor?
One thing I’m seeing in the docs is that, when you share tables between apps, the ‘Python name’ of a table can be different for each app with which it is shared. Are you sure that table_name is the Python name of the table in the app with that Server code?