Hi there Can you confirm which role your fake student has? If this user has been assigned with a role that allows the Preview quizzes[mod/quiz:preview]permission? This is what the teachers role has which provides the 'Preview' button rather than the 'Attempt' button.
Is it possible you have the test account assigned with a student AND a teacher role at either course, category or site level? This might affect the functionality for this user.
Hi there Can you confirm which role your fake student has? If this user has been assigned with a role that allows the Preview quizzes[mod/quiz:preview]permission? This is what the teachers role has which provides the 'Preview' button rather than the 'Attempt' button.
Is it possible you have the test account assigned with a student AND a teacher role at either course, category or site level? This might affect the functionality for this user.
I know it's an obvious suggestion, but is the quiz open to students? In other words, did you set an open date for the quiz that is still in the future, or a close date that is already in the past?
That wouldn't explain why a student sees a "preview" button, but it would explain why they don't see an "attempt" button. The more I think about it, the more it seems like your "test student" account somehow got higher than student level priveleges.