This is very difficult to imagine because the settlements on Greenland were small and fragile.Newfoundland never had direct contacts with Norway, but only through Greenland which, as has already been said, was vulnerable and lacking in many cases, and therefore was not in a position to adequately supply Newfoundland. In doing so, the Norwegen’s did not have a diplomatic relationship with the Inuit and the Indians they encountered, which was hostile to relations and was in the way of trade. On Greenland, it was mostly annoying, but Newfoundland could hardly afford to be able to do so, and no hostile neighbours. It is therefore not surprising that Newfoundland was abandoned after 10 years. Greenland was at the bottom of climate degradation, poor relations with neighbouring peoples, great distance to Norway, poor soil management, inflexible society and inefficient use of resources. On the other hand, the settlements on Greenland kept 450 years.
A survival of Greenland is most conceivable.Probably the Norwegian settlements had continued their marginally existence. Given that the Inuit continued and continued in the rest of Greenland, there was a high probability that the relationship with them had remained hostile, although it would be conceivable that they would try to cherry toe at a later stage (which the Danes eventually did). In Europe Norway was united with Denmark in the Union of Kalmar and Denmark itself on the basis of this Greenland; When the Norwegian colonies had survived, Denmark would undoubtedly have, at some point, equipped an expedition to tell the inhabitants (both Inuit and Noren) that they were Danish nationals from now on. It is interesting to wonder whether the Reformation would have had effect, but also here I think that the Danes would eventually have enforced them in Greenland. The biggest difference now is that fishing would probably have been marginally for a long time, because the Norwegian greenlanders did not ate fish.
Newfoundland would only have a chance if the relations with the Indians were more peaceful (it was 10 to 1) and there would be a better connection with Greenland and Norway (perhaps an extra colony on Labrador as a stopover or better ship technology).But with the then state of technology, the colony would always have remained small, a remote outpost of Norway. However, it is possible that in the times of the great voyages of discovery and colonialism following Columbus, the Norweis and Danes would also have spent more energy on discovery trips in the northern Atlantic region, taking an example to countries such as Spain, France, England and the Netherlands. Denmark (assuming that also Newfoundland would fall into the union of Kalmar) would then with Newfoundland have an excellent base to explore North America. It is conceivable that Denmark would have played a more important role in the colonization of North America. Perhaps not the French but the Danes were the great competitors of the English in America, and Danish would have become an important or even the first language in Canada and the USA.