This changes the inherent value of each of those stocks, which in turn changes the inherent value of the NDX, which in turn changes the inherent value of QQQ.
I'd have to check, but I think the fund has already bought the basket, and has sold the shares of QQQ. If I buy 10,000 shares, I don't think I buy them from the fund, which in turn buys another basketfull of NDX. I think I buy them from another holder/s of the shares. I'll have to look.