Bug#1004273: Correction: .bz2 -> .gz
The filenames in the DVD images appear to be Translation-??.gz,
but on the repository website it's .bz2 for most files, and
.xz for bookworm Translation-en.
A possible workaround I have not tried yet is downloading
Translation-en.xz from the repository path corresponding to the
.iso images (the URL is in the .jigdo files), and reprocessing
it into the missing Translation-en.gz.
I extract the DVD pool and dist files and remake them into a
local repository-style directory on a local disk that I can use
with apt locally. But it will of course not fix the images.