There is no consistency to any narrative that originates from Trump. First, they likely do not know for certain if he's under investigation. They would need to ask directly or have Mueller inform them once a certain point has been reached. That point is up to the discretion of Mueller. Could be indictment (I know, POTUS), interview, or any time prior. Willing to bet that hasn't happened. Yet. I also doubt that they've inquired. They don't want to know the real answer as that allows them the Trumpian wiggle room they need to play their disingenuous PR game. Which is exactly what they're doing by playing both sides of the "he's under investigation"/"no, he's not" argument. Using whichever one is more convenient at the time given their audience. And, as shown this weekend on the sunday morning shows, sometimes both for the same audience.
I seriously weep for anyone that falls for the stories this guy is pushing. You have some critical thinking issues or you're just blindly loyal to your own detriment. Maybe both. God (FSM, etc.) help you.