I’m sorry to hear this. What are your plans now? Drakes are nice to have but if eggs are what you want you’ll have to find some females. I never could keep my Muscovy drakes together once I brought in females they are fighters. Others on here may have a better experience but this was here. I kept 4 drakes and they each had 4-5 females but I had to keep them separated. Their coop had stalls so I could put each drake into his own bedroom at night. They climb so the top was covered with hardware cloth we made a top out of plywood and stapled the hardware cloth to it for ventilation in 2016 I decided to just keep one drake and I rehomed 3 Thankfully at that time they went to a home where they didn’t get eaten. I know many eat Muscovy but I prefer not to and didn’t want to let them go where they would be food. I get too attached.

I know this isn’t much help. Let me know what you think is best for your boys
I never know when I will have internet yesterday not at all. So I’ll try to check in when I can.
It's ok. So for now I will keep all, because anyways there are no females, but I am not sure what I will end up doing. We could eat them but I think it will be a very hard decision, so I just don't really want to get there now, I will try to think of other solutions first.
But one worry is I read that if they have not enough females, sometimes they try to mate with chickens, which they have access to here as they live together with the chickens. I don't know if that's the case but I read that online. Also, if I had to keep one male, I think I will choose the one with black head. Even though this one is quite aggressive to me as well, but I think the ducks living with it will have a higher chance of living because it defends and doesn't run away so quickly.
I have the 5 other ducklings which are supposedly Khaki Campbell (they don't look like Khaki Campbell ducklings except for one if you remember). I have put their picture earlier, and one of them at that time died after a bit, and another one disappeared somehow when I put them in the garden when I looked away. I found a solution for that, as I am using a secure place in the garden and used hardware net around to make sure it's closed, and we bought two more to replace the ones that died, and these two are slightly bigger than the rest. They are now living together, so maybe when we find out which are males and which are females, we can finally think about what to do with the extra males.
I also heard that if muscovy mates with other ducks, the hatched duck won't be able to reproduce and fertilize eggs, which makes it harder. Another problem is if I buy more muscovy, I have only seen them selling them babies, also without sexing them, so they might end up males again and I have to wait for long to find out. Also, I have seen a muscovy duck before for sale and it was way too expensive, while the baby is quite cheap and the food isn't too expensive.
Maybe what I could do is sell two of the males and use the money to buy a duck or two based on how much I sell them at, but I am not sure how long will it take for someone to buy, and I think a female duck is not enough for a male duck, as it needs more.
Thanks for your help.