Restrict the capability of Entering Timecards for a Certain Group of workers

We are using redwood enhanced time cards and have established HCM groups to assign timecards to.

However we also have workers who are not required to enter timecards (for example contingent workers). We have not assigned these workers to a HCM group, so they do not qualify for our custom timecard layout. However if they do attempt to enter a timecard, the Oracle seeded payroll layout appears, allowing them to submit a timecard.

We do not want this group of workers to submit any timecards, as they are not required to do so. How can we restrict them from entering a timecard in the system?