opendmarc-check is installed in /usr/sbin, manpage in section 8.
Would be nice if these files could be installed in /usr/bin and manpage section 1
For now I do this as part of my build process but it still remain a "special thing"
... And we know: "special things" tend to break some day in future :-)
Why? This isn't a user tool. Section 8 is for system administrator tools and daemons.