Meh, if you slot Heiskanen in next to Robertson on the point on that 1st unit PP, he easily has 20 more points.
Teams lose PP QBs all the time and the panic is more often than not unwarranted, because the team will find someone with a bit of chemistry to slot in on that top spot, and their points will balloon just due to being put in that position.
We are talking John Klingberg, not Nicklaus Lidstrom.
This reminds me very much of the Rangers losing their top D point getter by a large margin, Keith Yandle, who also, by the way, happened to be by far their worst +/- player. They didn't go out and trade for some aging expensive contract to fill the void. McDonaugh stepped up and rookie Brady Skjei stepped in and filled the void for the season, and the team didn't miss a beat, all while saving a lot of cap.