Interestingly, Food Data Central, a U.S. government site, says that seal contains 0 g of carbohydrate.
And EatThisMuch.com says the same:
CanadialSealProducts.com doesn’t seem to have an easily-accessed page of nutritional data, beyond talking about how much protein and how little fat seal meat contains.
The notion that the traditional Inuit diet simply had to contain more carbohydrate than we think has been around for a while, now. Likewise the notion that the Inuit have a genetic modification that prevents them from getting into ketosis (because everyone knows that ketoacidosis kills). But I believe these notions are based on speculation and not actual data.