According to Rob Rossi of The Athletic, Dubas and company are working on multiple situations in which they can acquire Karlsson, add him to the roster and stay cap compliant at the same time; take a look.
Scenario one is a direct trade with the San Jose Sharks. The second is a deal that involves a third team to offload defender Jeff Petry, but sending him to a team where he'll likely play. The third is a deal that would involve a buyout to make the cap space work. It sounds like whatever it is they have to do, the Penguins are all in on Karlsson
After getting the deal of approval from captain Sidney Crosby and another franchise cornerstone in Kris Letang, it's full steam ahead for Dubas and the Penguins.
In true Dubas fashion, it would not surprise me in the slightest if he finds away to overpay for Karlsson as long as he becomes a Penguin, Dubas will be happy