Everything stops after that right? There can be no saving grace for someone who was in the SS.

There are some rare cases where where individuals would breifly join SS divisions, specifically to fight the Soviets rather than due to alligence to the Nazi ideology. Larry Throne is a notable example. The First Galician seems to have had a significant number focused on fighting the Soviets in a similar matter, although elements of the division did commit atrocities in Poland. Canada's 1986 investigation into the division after the war concluded that there wasn't sufficient evidence to condem the whole group

Of course, "not found guilty" doesn't mean innocent. My point is purely addressing the, "There can be no saving grace for someone who was in the SS." I still think this is a ridiculous situation, that he should not have been invited unless they can confirm with great certainty that he was not a supporter of the Nazi ideology and did not commit any crimes. If they can't even check what division he served in, clearly anything more is outside their ability. Hopefully he is investigated properly given the spotlight, and extradited if needed.

Edit: Worth noting that this was a Ukranian division after the Holodomor. Its no wonder that many would be willing to join a war against the country that had murdered millions of their people already. For scale, its estimated that the Holodomor killed 3-5 times as many as the holocost in Ukrane.