Absolutely adorable. Look at those amazing ears. I just want to confirm that you got her spayed too? I know you already said “they” got fixed, but just making sure as the male can still carry viable sperm for a month after surgery. It also takes about a month for the hormones to die down and that will also be key in calmer less aggressive or territorial bonding behavior. (though no gaurantee there either — just less cards stacked against you)
I know they got along well before their hormones kicked in, but as you have discovered there is no guarantee. And you don’t want to complicate it with more fights — that can make it harder. I would advise that you let the hormones die down, let them get used to each other through the cage (though be very careful they can’t bite each other through the cage — i had one bunny bite another bunny very badly in the face — Bailey almost ripped Rucy’s lip off. (The vet had to do surgery to repair it). I ended up putting chicken wire between the cages so they could still smell each other’s fur and lie near each other.
Since your bunnies still get worked up when they’re outside of their cage with each other, you want to also let them just heal. After the fights, they will also need time to just associate good things with each other, so a few weeks of just hanging out near each other in separate cages might do that.
I know it’s much harder to take care of two bunnies in separate cages, but I would not rush it after what you have described.
EDITED Oops — posted about the same time as Peppypoo! Sorry for some of the repetitiveness.