Regrade button on "manage submissions" page is broken

The 'manage submissions' page shows all submissions and has a button to regrade an individual (right side the arrows in a circular cycle). This is broken. Dustin and John are 'instructors' on this a staging course and can try the button here:

https://autolab.encs.vancouver.wsu.edu/courses/swtest-s19/assessments/helloautolab/submissions

it gives a 404.