These two things are very different. The support I pushed to
cups-filters is a CUPS-side rendering of documents, which I'd rather
see homed at cups-filters. The support packaged separately in
printer-driver-indexbraille is provided by the manufacturer itself and
has an entirely different approach: it just sends the document to the
embosser and let it do all the rendering. That approach seems to me
much less interesting for CUPS (there is no support to be shared with
other drivers for other embossers, for a start), that's why I didn't
push it into CUPS. The two options can make sense, so a user may even
want to have both installed and use one or another depending on the
cases at stake. Personnally I find the CUPS-side rendering way more
flexible and convenient.
Samuel