here is what you are affirming to when you file a return as a preparer "Under penalties of perjury, I declare that I have examined this return and accompanying schedules and statements, and to the best of my knowledge and belief, they are true, correct, and complete. Declaration of preparer (other than taxpayer) is based on all information of which preparer has any knowledge"

So, you are willing to affirm to something you know is wrong???  Enabling a check mark would seem to pale in comparison to committing perjury on a tax document.