ABC and NBC have failed to cover the story as of Monday June 16, and only CBS This Morning reported on the emails on Monday but their evening news program ignoring the IRS alongside ABC's World News with Diane Sawyer and NBC Nightly News.
Unless there is something missing, your links aren't to broadcasts on their evening news programs prior to June 16, which is what the OP was talking about.
Did Diane Sawyer and NBC Nightly News report on it before June 16? That's exactly the 2 shows mentioned in the OP. Unless your links contain footage from either show before June 16, then the OP is correct.
“I think if Thomas Jefferson were looking down, the author of the Bill of Rights, on what’s being proposed here, he’d agree with it. He would agree that the First Amendment cannot be absolute.” - Chuck Schumer (D). Yet, Madison and Mason wrote the Bill of Rights, according to Sheila Jackson Lee, 400 years ago. Yup, it's a fact.