Sure, you can.
Log in remotely with PuTTy using the admin account and password. You will be presented with the server console menu.
Select option 6. Access server manager. Confirm that you want to login using the Elinks text-based browser.
Login with the admin account. Use the TAB key to navigate to the left menu pane and select the User Vacations option. TAB to the main screen listing all the users. I think you know where to go from there ...
PS: After logging out from the server-manager, you can quit the Elinks browser by pressing the "q" key.