Have you actually logged as the student to see what shows?
Do not use the Moodle "Switch Role to..." option.
Log out of your session and log in as the student using a password.
I am not sure if this was mentioned or if you already know this, the black text that describes the restriction is only for your eyes. The students do not see it no matter what any of the eye settings are.
The eye to the right of the assignment, hides it totally.
The eye within the restriction setting hides the assignment based on the group setting.The settings can cause it to show until a time/date and hide until a time/date. It can be set so that one group does not see the assignment for the other group.
It is difficult to see if you know this already or if I am not seeing your situation.
Then again, I just might be a bit helpful here. (: