Yes, I had to cull pretty hard. In fact that's why I have selfs and otters, instead of coppers, chinchillas, and my very favorite, reds. All of the agouti Satins I had for several years were n-a-s-t-y.
Hopefully the breeder will have sympathy for your situation and give you a trade. I know some bigger breeders have biosecurity concerns, though, and don't necessarily like to risk bringing rabbits back once they've left the property.
I have no idea what your buck's particular problem is, of course, but for the time being, there are some things you might try to encourage him to calm down a little.
If you can isolate him from other rabbits, that might help. I don't mean take him to a different building (though that might actually help), just make sure there are solid dividers between him and all other rabbits. It doesn't sound like you have any other males, but I've had bucks that were driven to distraction by being able to see others.
If he's lunging/biting out of fear, maybe giving him a hide, like a three-sided box with no floor, would give him a place to go to get away from you. The problem with that, though, is that when you bring him a doe to breed, she'll probably use it to hide from
him, so it would need to be removable or able to be blocked off.
Keeping him on a water bottle and getting a feeder you can fill from outside would make it possible, at least in the short run, to take care of him without having to do what he seems to think is invading his space. Yes, rabbits tend to drink more from crocks, but many of them do just fine with bottles.
Giving him treats (grass, dandelion leaves and flowers, chickweed, etc.) through the wire might eventually help him understand you're the source of good things rather than a threat. Start with just dropping the stems through the wire on top and sweet-talking him. Eventually he'll probably come up to take the stuff through the side wire. A little patience can go a long way; resist the urge to punish him, which just seems to escalate things.
Likewise, bringing him does to breed might also get you in his good graces after a while. I have had bucks that weren't especially friendly, then after I'd brought them a few "dates" they couldn't wait to see me.
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But if your buck had never been bred and you brought him his first does, he may be just over-the-top excited. If that's the case, he'll probably relax after a few more breeding attempts. Alternatively, if the super-assertive older doe really bothered him by mounting him, he may be responding aggressively for that reason. Either way, he may very well mellow out, at least a little; if you just recently got them all, he's probably still figuring out where he is and who and what is safe. I still wouldn't keep him, as I want my rabbits easy-going right out of the gate. But it might buy you some time while you find another option, and make his life, and yours, a little less stressful and more pleasant in the meantime.