I’m not a friend of those systemd vs sysvinit discussions, so please leave them away in favor of finding a solution.
In terms of sysvinit support, you also might want to open a feature request in the Director project if not already existing. For a quick solution, you might want to look into other tools/scripts how they do it, and copy the ExecStart line from the Director. Maybe it works, maybe not.
Cheers,
Michael