Everyone is blaming the ref, which is pretty interesting, even the people who saw it.
I watched it before I heard of the fuck-up and this is what I saw:
Nattie puts on the sharpshooter. AJ is like 'ow dis hurts'. Then Nattie releases the hold. AJ starts to tap. The ref is like 'uhmmm'. There's awkwardness. Nattie goes to have her arms raised, like she's covering for the mistake. They repeat the finish.
So I watched it again and can confirm Nattie stops the move before AJ taps out.
Can you normally hear someone tapping out when you can't see them? Maybe someone gave the go-word.
It's not the ref.