I don't see why he wouldn't be a PK beast. That's the easiest for guys like him. He was on PK1 right away in Laval.
And I don't really care for the PP, that's Hutson's job.
I wouldn't read too much into that. Laval is the Habs farm. Coaches would probably risk their job if they refuse to give Habs top prospects special team ice time. Also, AHL isn't quite the same as NHL.
In Switzerland there have been many games where Reinbacher led the team in ice team despite playing no or very little special teams ice time. Reinbacher had four head coaches in Swiss pro hockey but none of them really relied on him for PK or PP despite leaning on him heavily at even strength.
Now in NA teams are usually dressing 6 defensemen (vs 8 in Europe) so obviously Reinbacher is gonna have to help out on PP and/or PK as well and I'm sure he's gonna be perfectly fine doing that. I'm just not sure he's ever gonna be elite in those situations. It's possible but I think he's gonna be a guy you primarily want on the ice at even strength for as much as possible.