I understand the need to keep things unique to paid DLC maps but even if Rock Drakes are added, Reapers are still unique to Abberration and adding more Wyverns would add variety while Sorched still has the Phoenix. If the map already isn't canon, what's the harm in adding Extinction dinos while you are at it?
Again, I understand the need to have each map have a unique dino, but you already took the frost wyvern and griffin from Rag so why not include a few more in areas that make sense?