IT sounds like using Roles and creating users that do not have access to main menu would serve your needs more efficiently. That is a lot of work just for preventing someone from seeing a report. If you feel they need access to main menu for some reason you can just disable the ability for them to click on Reports button. Even tho they would see the button on the screen they would have ZERO ability to actually access any reports or view them.
Personally I only allow my employees to see and operate the POS screen. In the case that my employee needs to pull up a previous ticket I allow them to view the ticket viewer from a custom entity screen and it is mapped to its own department. This allows them to view tickets without having to navigate to Ticket Explorer using main menu. They simply click on Ticket Explorer department button.