They didn’t use skis, but Kayaks.
If you know anything about the area, it’s a maritime culture, not a land culture.
The most logical trail across the North Country to Greenland goes right through the heart of where the Polar Bears live AND EAT during the warm months.
The Inuit at that time, according to archaeological evidence, generally kept within 50 miles of the coast wherever they went in any case ~ their technology having its best effect in that zone.
They'd have had kayaks for water crossings if they encountered any, but also sleds with dog teams ~ hundreds of dogs!
I'm talking about this trip being taken in winter, or late Fall, overland. The conditions wouldn't have been as rugged as other's encountered centuries later in Antarctica, and dog teams in the hands of Eskimos would have worked quite well.