Yeah, no. I'm the same height and body shape as her, and when I looked like what she looks like in that video, I was around 425 pounds. She's nowhere near 700 pounds, and I doubt she's even 500.
She's just another fat chick with a camera who figured out that she could make a buck off of throwing around outrageous numbers and bizarre fantasy scenarios to draw some shock value attention from the media and get the fetishists sniffing around her clip store.
It'll play out one of two ways. She'll work her 15 minutes, make some pocket money, and disappear. Or stick around for a while, gain a bunch of weight, get dumped by the boyfriend when he has to start doing ass wiping duty, then boohoo to the media in hopes of getting a second payday and a weight loss intervention endorsement.