[experiments] Sharing not working properly with experiment containing private objects

For some reason, I'm getting a bogus answer when trying to share an experiment with a single user.

The experiment is private and uses algorithms which are privately shared by some other people. So, I guess I should not be able to complete the action (that bit is correct). The issue is that I'm not informed this, but rather a bogus screen:

The underlying reason is that some of the components this experiment depends on are privately shared.

Looking at our swagger interface and trying to hit it with the sharing request, I see what is the issue:

This should be correctly reported back to the user instead of the screen I got above.