Magnetic deviation in Resolute Bay is sth about 18,5 degrees W, which would approximate match this error. It should be kept in mind that 18,5 is in real life updated to 26/09/2021. We dont actually know which date equivalent matches magnetic north in MSFS (it drifts about 25nm each year in real life), but I will check on that during my next session. I can’t belive tho, that they implement a live magnetic north update in the sim. So I think we should call it a bug, as long as other planes can perform this approach correctly.