No team has traded down out of a top 5 pick in the Salary Cap era. The last time it happened was at the 2004 draft, right before the lockout that resulted in the Cap.
Top 5 picks have become way too valuable under the Salary Cap.
The only top 5 picks that have moved in the last 20 years were ones where the team that gave up a top 5 pick did not know they were giving up a top 5 pick at the time they made the trade (the trade was made prior to the season that resulted in the pick being a top 5 pick). And they all involved a star NHL player getting moved in return (Karlsson, Duchene, Kessel).
Teams only trade down if the player they want is one they think they can still select with a later pick, and that's not going to be the case for anyone picking in the top 5 this year, given the drop-off in talent.
The idea of trading up into the top 5 of the Draft just because you have two first round picks is a pipe dream, not a realistic outcome. I'd put better odds on the Pens getting into the top 5 via the lottery.