Read.
Isotope analysis of teeth can reveal clues about a person’s drinking water, and in turn the climate they came from, said Jane Evans, an isotope geochemist at the survey.
“What we found was all of these guys came from a climate that had to be colder than Britain ... probably Sweden and Norway,”
At the time this guy lived (probably 900 AD) the Vikings, meaning Old West Gothic speaking people, were just then learning to scale up the boat hull they'd discovered in Lapland ~ which made it possible to sail in Arctic and North Atlantic Waters in the open sea.
I'd say right off hand that the guy with the far North guy wasn't Indo-European at all ~ but rather was a Sa'ami
What that means to me is the folks doing the tooth analysis forgot they are dealing with a "race" which had been living separate from other Europeans in that region for about 15,000 years and had developed some rather striking differences.
Among them were the "teeth". A Finnish study found that Skolt Sa'ami were missing 18% of their adult teeth simply because they never formed. You can find several references to this under articles containing the expression"dental displasia". Seems to me that just counting teeth would have clued them in to that one individual's identity.
It's possible these studies haven't yet caught up to anthropologists though.