I'm not sure if there is a way to help the NCR within that quest. I know you can, however, still kill Mr. House after you give him the platinum chip.
Once you give house the chip he will instruct you to go and ask the Boomers to help him in the upcoming battle. Which the NCR has also done.
The way I did it was: I gave house the chip, got the Boomers to agree to help me/NCR out and then I killed House and put Yes Man into the computer.