Which solitary journalist are you referring to?

Where are the missing commas and full stops?

He’s not a journalist, he’s a twitter guy and probable con artist.

"X did Y on a Z he thought would explode" is an efficient sentence but I can understand the grievance, because reporting should be clear and not take shortcuts. I think oxford commas should not only be obligatory, but enforced by a special linguistics task force with MP5s and tactical gear.

In response to your edit: if you insert the word "that" after "plane" it might make more sense.

Karoline, Leavitt, will leave, her position, as the White House press secretary, at the end, of this month.