Fritz Hermann/Bill Douglas

Can someone explain the following:

I have the Medusa "full-length" Blu-ray edition of Leggenda, which has a choice of Italian or English sound and Italian or English subtitles (just like the DVD I had before -- this being one of my favourite movies of all time). My wife and I watched the English version which I would consider the "original" (the movie obviously having been filmed mostly in English) and turned on the English subtitles just in case, as neither of us is a native speaker.

We found out that the English subtitles have very little relation to what the English soundtrack is, which was very irritating at times (they are probably a re-translation from the Italian soundtrack). It uses expletives when they aren't used on the soundtrack and vice versa, synonyms when none are needed, and at times insert lines that are not spoken at all.

What I am wondering about in particular: The band leader ("Just the normal notes, please") was called Bill Douglas in the English soundtrack version, speaking with what I took to be a Scottish accent. In the subtitles (and in the cast list on IMDb!) he is mentioned/listed as "Fritz Hermann" (and thus, as a German), and also quoted as saying things like the perennial cliché "schnell!" etc. when he actually says no such things at all.

Does anyone know why this (really secondary) character changed his name and ethnicity from one version to another?