I watched the second airing of this episode but didn't record it so I'm having to rely on my memory.
I thought Helen made poor use of her power chip when she had only a 3,000 bet out. I would think having a power chip should give you a much better than 50% chance to win a hand before the cards are delt; therefore bet the max if plan on using the chip.
As the 2nd knock out card was approaching and Ken was drifting toward the low end of the chip count, why not put out a max bet before the knock out hand and plan on using the PC if necessary and climb back toward the top (if the hand wins). That way when the knock out hand comes your not eliminated even if you win the hand as Ken was.
If you think the knock out hand will be around hand 20 and your trailing then put out a max bet on hand 18 - to give yourself a margin for error.
Someone needs to calculate a basic strategy for use of the PC chip and the player advantage when he has the chip.