That throwing the red flag when it was already being reviewed stops any review is the stupidest penalty out there. I've seen coaches throw red flags when the play can't be reviewed and they just pick up the flag and explain it to the coach, but somehow doing it when it is already being reviewed is some sort of actionable offense? Why? How would doing so give someone an advantage or cause any harm to the game? It wouldn't even delay things because it's already being reviewed. Usually rules have some basis in reason. I don't see this.
Shouldn't the coach of the Texans just thrown the flag instead?