I generally agree with the rule and the reasoning given for it. But I think the worry about the "Fake" suffix here is missing a crucial point.

This is test code. In test code, the "business" at hand is exercising the production code. To put it another way, test code doesn't have the same business domain as the application code.

Therefore, in test code "Fake" is a domain-specific term, and it is perfectly appropriate as part of a class name.