Could some kind #FreeBSD / #BSD user show me an invocation of the "mtree" command (and its input file) that allows me to check/update the ownership of specific files inside a nested directory hierarchy ... but where I'm not interested in all files?

I /feel/ it should have something to do with the "Full" line type mentioned on https://man.freebsd.org/cgi/man.cgi?query=mtree&sektion=5 ... but I've been unable to get something like this working:

#mtree
usr/local/etc/sudoers.d/my-test type=file mode=0440 uname=root gname=root

Even with -e, "mtree -e -p / -f path/to/this/mtree" complains about "usr" not being specified. How can I make mtree not care about directory entries that I /know/ will exist, and only check the specific files I list?