That title's such a misrepresentation of what was said. She threatened a deadman's assassination if she was assassinated first by Marcos, which could be a legitimate risk. She said nothing of the sort about that being on the table in any other scenario. In more easily-conveyed words, "If you kill me, your days are numbered."
The title's not just clickbaity, it's a misrepresentation to the point of bordering on DARVO tactics. You might as well publish a news article on August 10th 1945 that says "Japan mad at US".
Sorry, most of this vitriol is directed at VOA. Not sure what the submission guidelines are on NTO but you might not be able to change it. It would've been better if they ran with something along the lines of "Philippine vice president promises revenge assassination if president assassinates her".