Welcome to the forum!
If the glyphs are working in an older version of Inkscape, that would seem to imply potentially a new bug. But as I answered the original user, this is not an area I'm very familiar with.
If no one else answers in the next couple of days, I would suggest contacting developers. This message tells how to contact developers, in different ways:
https://forum.inkscapecommunity.com/index.php?topic=628.0 So whichever way is best for you.
Out of curiosity, I searched using Windows Character Map, and don't find these unicode characters in DejaVu Sans, DejaVu Sans Mono, or MS Gothic. Although I'm on Windows 7, so maybe they just aren't created yet, in Windows 7 ?
In the Inkscape Glyphs dialog, set for DejaVu Sans, I do see a lot of glyphs that don't display (the box with what looks like 4 tiny numbers inside, but they're so small, I'm not positive if they are numbers).
Well anyway, if no one else responds here within a couple more days, please try and contact either developers (per info in the linked message), or more advanced users (via User mailing list or chat, see linked message for details).
Sorry I can't be more helpful