Hungary appears as a belligerent on the Axis side of this article, yet it really doesn’t mention where the Hungarians fought the Allies in Western Germany.
The Hungarians were mostly worried about the Russians. They were anti-partisan adjuncts to the Germans in Russia, Poland, and Yugoslavia.
The Germans, suspicious of Hungarian intentions of leaving the war (which were justified) took over the country in 1944 – and immediately began sending Hungarian Jews to death-camps. They put a puppet ruler in charge. The Hungarian military fought against the Russians as they moved into Hungary with the Germans. Some retreated into Germany when Hungary fell, fled west, and surrendered to the Americans (a general plan by Germans and their allies by this point).
So, I don’t think we can say the Hungarians ‘fought’ the Western Allies so much as threw down their arms and surrendered to them. The reference in wikipedia is, I believe, to that.