What is your defence?
It comes down to who is believed then. It isn't really possible to tell in this forum.
If there is CCTV and the bouncers maintain that you attacked them then that is evidence that can't be ignored.
The problem with situations like this is that you can only use reasonable force to defend your husband if the conduct towards him was unlawful.
It is quite unlikely that they are going to accept the bouncers leapt on him for no reason at all.
If your defence is that you didnt cause the injury though then remember that isn't relevant to common assault.
They don't have to prove that injury was caused. They just have to prove that you laid hands on them unlawfully.
Although, of course, if the allegation is that you did cause that injury then it does weaken it if you can establish that you did not.
Can I clarify anything for you?