Yeah, too harsh. I agree with J.B. that your husband could have been more mature. In effect, you and Dad are trying to manipulate your children's feelings through guilt and punishment.
There's nothing to be gained by that except children who can be manipulated (eventually by their friends and spouses). It's fine to give consequences for bad behavior, but kids have a right to their feelings, which include a preference for whatever it is they are already doing. They shouldn't be required to manufacture an insincere response. (I don't think it's wise to require a child to say "I'm sorry" until they genuinely feel sorry, either.)
Kids are extremely immediate in their wants and needs. If I had an inkling of when my husband would arrive, I might have instigated a little welcome-home celebration. If I didn't know until he walked in, I would have gotten the first hug and kiss for myself, then given Daddy an opportunity to go sit down with each of the kids and tell them that he missed them and was delighted to see them again. The whole dynamic would have been so much happier for all of you.
It's not too late to have a small chat with your kids and apologize for overreacting. Tell them what YOUR immediate feelings were (disappointment, "sad for Dad," etc.). Then give them a chance to share their own reactions, which, for them, were perfectly legitimate. That's a great lesson by example, too. Your husband could do the same, if he's so inclined. I'll bet your family ends up having a happy evening.