If you watch the video, you'll see that she knows that she doesn't have a 3 - she checks her hand before she calls and also a player at the table asks her if she has a 3 and she says no. Then afterwards she did an interview in which she explains how she thought she had a 3 but that doesn't match what she said at the table.
> She was only 47% to win the hand after her call of the all-in bet and while the play was marginally +EV, it wasn’t much.
It's not marginally +EV to call given the pot odds and she doesn't need to know her exact equity to be cheating, she could be getting binary "you're good" / "you aren't good" signals (and that's much easier to transmit and read without being noticed).
The play on the turn is way too ridiculous. The other thing is why did she return the money after the hand if she won it fairly? Sure, maybe she was intimidated but to me it looked like she cheated, she realised that she's in over her head and tried to make the whole thing go away by returning the money and coming up with a story about the hand she thought she had.