You sent me on an enjoyable wild goose chase but it appears that only ß and ff are in unicode: tz, ch, ck have to be handled completely in rendering.

I have my music teacher's German schoolbook from around 1915 and it lists them all as letters (the whole book is in Fraktur). I have various old books in Fraktur and once could read them. I imagine that if I sat down and tried to read one it would come back, but at the moment I have to thin a little to read just the titles!