The recent college admissions scandal mostly charged parents with wire fraud, if I recall correctly. The fraudulent part of their conduct consisted solely of untrue speech, representing to a school that an SAT score was earned by their child when it wasn't, or representing to the College Board that the person taking the test was their child when it wasn't.[1]
[1] There were other methods, but the two I list here seem in my eyes to consist exclusively of untrue speech. There were also fraud charges associated with representing payments as donations to a charity (for tax reasons) when they were meant as quid pro quo payment for services. If the tax fraud was the basis for every fraud charge, I'll admit that this example is invalid.
Wire fraud requires an intent to defraud ("obtaining money or property"). In your example, the defendants were all free to lie about someone being their child. They were not free to lie about it for the purpose of defrauding the College Board, which meets all of the standards of Brandenberg (inciting imminent lawless behavior that is then likely to occur).
[1] There were other methods, but the two I list here seem in my eyes to consist exclusively of untrue speech. There were also fraud charges associated with representing payments as donations to a charity (for tax reasons) when they were meant as quid pro quo payment for services. If the tax fraud was the basis for every fraud charge, I'll admit that this example is invalid.