Just to say that I recompiled org and reloaded and following a citation now works "out of the box". Caveat: I haven't restarted Emacs (it's my window manager and hence there's significant inertia against exiting Emacs...) so I'll verify everything next time I restart (which could be some time...).
Now back to writing my paper! Thanks again, eric PS - writing academic papers fully in org gets easier all the time. org-cite is the latest greatest addition! Thank you all. -- : Eric S Fraga via Emacs 28.0.60, Org release_9.5-163-g4eab5b : Latest paper written in org: https://arxiv.org/abs/2106.05096