Yes that is correct. The catch is that you MUST have a local ethernet interface for the DHCP server to function, even when you do not desire to use it locally at all.
That is even so for ISC DHCP on Linux. You cannot have a DHCP server that is ONLY a server for relays.
But you can use some dummy interface probably even a bridge with no member ports, with an ADMIN MAC on it (dummy value).