They could create a second combat cross. While it's true that Gandolfi disappeared ... that doesn't mean he's dead. And the Belmont Clan can still exist. They can retcon a child into the mix or name another orphan "Belmont" just like they did with Gabriel.
This post is 100% opinion unless stated otherwise.
I'm sure in this new timeline they are going to use this as Dracula being the 1st Belmont then use some plot twist/retcon where he had many children while being a vampire or even not who grew up and of course had their own children but always fought him since he'd a Belmont out of control sort of a family secret and their responsibility and use it to explain why Belmonts always seem to have super natural powers and what not. Basically Alucard's story... sort of.
They didn't name him Belmont for nothing I'm sure. That would be stupid.