Interesting post. But Natalie White was never even considered for H vs V--coming straight from Jeff Probst's mouth.
However, this season did seem a wee-bit scripted. And it wouldn't surprise me if Parvati really did know about Russell before the game, but to me there is no proof beyond a reasonable doubt.
It's all speculation at this point. It doesn't make sense to me though that Erika Shay would be on location of Samoa and would be allowed to bring Parvati along when she was being considered for Survivor 20. You'd think production and crew and Mark Burnette would be on top of that.
I hope this is addressed in Parvati's interviews; how she deflects the question or answers it may give us a little more info to speculate on