In a recovery mode root console
no such file or directory
cd /; find -name passwd (no results)
I don't see passwd, passwd-, shadow, shadow-
$ or # busybox
Throws up a list of commands that busybox handles, but passwd is not there, unlike standard busybox
# busybox passwd (Which was me trying to be clever)
returned nothing :-O? Then I ran out of ideas and posted here.