What? You think the Penguins are going to trade one of the top 5 or 8 best players in the NHL in Malkin to the Kings and get a cap dump of Brown in return in the package? That will never happen in a million years no matter how you spin it. Brown's cap hit is $6 million a year until 2022. Pens will never take that trade even if Carter is coming back at a reasonable cap hit.
If you want to make a serious offer to the Pens for Malkin it looks more like this: Toffoli, Kempe, 2017 1st (and that might not be good enough either). Or its something like Pearson, Carter, 2017 1st. As much as I would like Malkin on this team, I would not be willing to make either trade, which only gets the conversation started.