@Amalathea You can do pretty much exactly what you want. You can make any sim you want a Grandmaster vampire but I'll take a bit of play to do that. You didn't say what system you run the game on or if you use mods. So I'm going to assume you run on a PC. If you use just the ingame way, all versions should be able to do it. If you do it by mods, then that may just be on PCs.
All a Grandmaster rank is, is a vampire that has been ranked up by gaining enough experience to level him up to the top rank. All vampires can be that level if you want. There is no "King of the Vampires" so to speak. But there is nothing stopping you from playing like there is one. If you only want a certain sim to be a vampire in the game, then all you have to do is use Vlad to turn whatever sim you want to into a vampire and play that sim to get him leveled up to the Grandmaster level. You don't even have to do it in your main save. You can do it in another save and once you got him leveled up, save him to your library and import him into your main save. Of course, that sim will have no relationships and you'll have to recreate them. Then delete Vlad and any other vampires you already have and you've got your "Grandmaster". Then use him to create the other vampires you want and leave them as playables in a household and don't play them so they don't rank up. But, that's hard to do if you want them to have some of the perks because it takes that level to get some of the higher level perks. It takes quite a bit of play to get all the perks.
If you just have the premades in the game, the game does seem to create NPC vampires. But after a while, I've found that it seems to stop at some point once you've got a certain number. Don't know what that is. I have a bunch of playable vampires and very seldom do I get an NPC one now. But if you see one you don't want, go to manage households and find and delete them. You can make other vampires with your Grandmaster vampire so they show that your vampire is their creator (I forget the exact way it is worded) when you check them in the rel panel. That will always show even if all of them are at the top rank.
You can also do most of this through MCCC and the UI Cheats mods except the for the relationship tag for who created them. Might be able to do that too but I just don't know. MCCC can make any sim a vampire. I think UI Cheats can give you the points for the perks but don't hold me to that as I've never done it that way. I play my vampires to get the points and buy the perks.
Hope this helps you.
