Russia Ukraine war, page-35778

Well as you know, the Ukrainians initially welcomed the Germans in WW2 as liberators from the Stalinist yoke.
Until most realised that the Germans were worse- certainly if Jewish.
Ukrainian Nationalists and Auxiliaries then aided and abetted the Nazi is their extermination of Jews , Poles, Communists, intelligentsia and ordinary Ukrainians deemed "hostile" or of harbouring partisans.
There are many well known and high profile examples of extremely sadistic Ukrainian death camp guards. Not Polish, but particularly Ukrainian.
The Galician(Ukrainian) SS was a well armed and notorious force. They surrendered to the Allies, were imprisoned in Rimini and in 1948 most of them got tickets to the UK, America and Australasia where most married and settled.
Like most of the SS, very few were held accountable for their crimes.
Having said that many innocent Ukrainians were taken as forced labourers back to the Reich and were able to leave for the west after the war.
Perhaps you should ask your grandfather. If he left from Rimini, he was Galician SS.