If I tweak student's permissions to allow them to add/edit only their own questions to the questionbank, everything works and their are prevented from checking questions created by others.

However, that student is able to set Show question text and this will show the question content, except for the choices.

Discussion: https://moodle.org/mod/forum/discuss.php?d=463879

I agree with Tim, if you aren't able to see/edit questions they shouldn't be on your list.