Hmm this is a really interesting situation and I have a middle ground perspective here. I don't believe blaming your husband is going to be that effective, just as I don't think punishing your child for days on end is going to help either.
Firstly I am curious as to why that particular punishment and the reason for the duration. Your husband may have a valid reason why he thought that was a reasonable consequence and the only way to find out is to ask him. We don't know what his background is, he may very well see that as "normal". That said, I can totally see how utterly frustrating it is when others set consequences and leave you to follow through. It doesn't sound like either of you are on the same page here and that may become an issue as things move forward. It is fine now when your son is less aware but once he hits 6-7-8+ years of age he will see those chinks in the armour and exploit it (as all children do!)
At the same time, I'd really avoid undermining your husband. Why? Because once you give in, it will make it much easier for boundaries to be pushed in the future. That is a one way ticket to a monster child in the future.
From a behavioural perspective ideally you would want to shape the behaviour of your son by removing something he likes for a short time. It MUST happen immediately after the biting. If you do it even a day after they won't make the connection between the behaviour and the consequence. The punishment should be proportionate to the behaviour - a bite, for me, should entail having to not have the toy for an hour at his age. Once you give it back you say "you had this taken away because you bit me and that isn't nice. You can have this back but it goes away if you bite again".
Punishing unreasonably leads to resentment and is not effective in the longer-term. You want to reinforce the positive behaviour (praise, reward) and shape the bad behaviour (short term withdrawal of pleasant things).
This is SO hard, especially if you have had enough of listening to the whining but remember - the tantrums and whining is designed to get what he wants. This is how humans learn to express emotion. I wouldn't punish a tantrum - its a child's way of understanding what works and what doesn't. Punishing a tantrum gives the message a child's inner experience is bad and wrong - this will likely lead to over-control of emotion which is really not a healthy place.
I'm also curious about whether your child understands why he shouldn't bite? Explaining this will help him see the perspective of another person - baring in mind at his age he will have little concept of his behaviour and the impact on others.
Good luck! I try to get a middle ground here. Demonising husband isn't helpful because it will inevitably lead to conflict and misery. And taking the blame yourself is also not helpful because you have every right to express a view.
B