Not sure what the laws are in Sweden, but after 60mi/km I am pretty sure that was beat on pretty good, by a fairly good sized individual. Or, as noted in the translation, a rock or stump...which, though he states he didn't hit, can HE prove that? I don't think the burden of proof lies with Polaris. Warranty is for "normal use," and denies "normal wear and tear" if I remember correctly. If he can't prove "normal use"---a term which means normal according to GROUP consumer average, he doesn't fit the warranty outline...sorry. And, should this go to court over the advertisement, Polaris, I am sure, will come up with several first hand witnesses who are able to back their defense. He takes this to court and he most likely is going to loose. It will cost him more that just sucking it up and fixing the thing.
And for him to state that he has never seen anything like this on sleds before means he forgot about the late 90s (or earlier I guess too). Before much attention was paid to the running board. Perhaps he never rode during that era. Those running boards were pretty bad with regard to holding up to abuse. Heard very little whining in that era, just a lot of bracing and fixing.