I won't weigh on if AC will allow a home-generated/mobile boarding pass in this scenario as I simply don't know, but I would feel slightly more confident is the Turkey-Denmark flight is on SK rather than TK, as both SK and AC use the same airport system (Amadeus CM) and SK would be in a better position to join the itineraries together, verify the ticket, and attempt to get a boarding pass, if all else fails. TK uses a different system so this may be harder to accomplish.