In the future if someone is doing something wrong, clearly wrong, and potentially harmful, if they don't heed your suggestion for appropriate action then you need to relieve them. As in, GTFO of my way *****, go review respiratory physiology and then come back and we'll talk. You're the physician, they're the technician. Try to be very concrete, like "hey RT person, ventilate at an appropriate tidal volume at a rate of 15, that's one breath every 4 seconds, with a 1 to 2 I to E time." That's an order they are obligated to follow. Don't let people F up when you know they're Fing up. And if they give you BS about accuracy, etc, correct that as well. This person will continue to be a pathetic excuse of an RT because she still thinks she was right, and she obviously was not.
Cheers!