I don't think your conclusion is correct that MutterKrauseBuch is being used for the list numbers in the first ordered list.
I have noticed in the past that, when reading standard epubs on a Kobo, the list numbers always appear in some strange "twisted" font. They look to me as if they have been artificially skewed and stretched slightly. I agree that it does look a bit odd. I've always assumed that the Kobo Adobe reading app is "doing something" automatically, but I don't know what or why.
As to what you can do about it ... I don't think the Kobo kepub reading app has this quirk ... but that's probably not what you wanted to hear
