This whole "illegal naked short sales" story recently is a conspiracy theory, not a valid theory, so you're not going to get a source.

The main difference between a conspiracy theory and a valid theory is that a conspiracy theory is non-falsifiable; any evidence to the contrary is dismissed as "fake news" or "the deep state is hiding the evidence".

In your example here of "they testified to Congress under penalty of perjury", the response will be "Ya, they lied, because they knew the whole system would back them. They faked all of the records that show that they didn't actually do it!".

Now this isn't to say that a conspiracy theory can't be right in the end, but that still doesn't make it a valid theory.