Moving this from Home & Home Office Community Help to the Business Community section for attention.
I only know of one way to do it and that would be to add a user-defined PUP detection based on the name of the file. In this case you could add "celtetris.xls" to the policy and then VSE will smack it. You may also want to get with your Group Policy Admins to see if there is something that can be done on that front.
Otherwise, what you are really looking at is a management issue. Management needs to crack down on people playing games through behavioral policy with stiff consequences.
I wish I could help you more.