How to create a list of missing submissions

How to create a list of missing submissions

I have a app that i made to capture time for our employees. I have an employee list that I am working with, so there is an established base list of employees. 

What i need to do is create a function (or a button in a stateless form) that will allow me to generate a list of employee who have not yet submitted their timesheet, based on a date field (Week_of).

Any help would be greatly appreciated.

Thank you in advanced.