Well I can't speak for their current opinions on Nazi Germany, but I do know that Kim Il Sung described them as being "morally inferior" and said that they lost WWII because they had "abandoned all moral principle and driven their caterpillar tracks roughshod over the good and beautiful".

Also, fascism is viewed to be the anti-thesis of the juche ideology; so Kim Il Sung wrote a lot about how destructive fascism was, which he viewed as being best exemplified in Nazi Germany.

He wrote in "Abuses of Socialism are Intolerable":

Totalitarianism served as the political idea of fascist dictators. Notorious Hitler in Germany and Mussolini in Italy used totalitarianism as an ideological tool to justify their fascist dictatorship. The fascist dictators stamped out even the most elementary democratic freedom and rights of the masses of the working people and enforced unprecedentedly tyrannical polices, behind the misleading name of "national socialism", claiming that for the sake of the whole nation and of the state no working class movement and no class struggle could be permitted. The reactionary nature of totalitarianism is that the interests of the working people are sacrificed for the sake of the rapacious interests of the reactionary ruling class under the pretense that the individual should be subordinated to the whole. What is meant by the whole in totalitarianism is not the whole of the popular masses by a tiny handful of privileged circles such as monopoly capitalists, major landowners, reactionary bureaucrats, and warlords."

So it's safe to say that they still probably don't think very highly of Nazi Germany.