I thought it was the Croatian SS?
No, Croats Black Legion was in Austria (near Slovenian border) in May '45 & they didn't surrender to British or anyone else.
Commander was general Rafael Boban, in Korean war he was U.S. Army colonel, died in South Cali in 1978 (!?).
Very intriguing WW2 fighter, just like Oto Skorzeny or the Belgian SS Col. Leon Degrelle.