I'm Lucy, and I'd be happy to answer your questions today.
Unfortunately, yes, he still has to pay. Child support is an obligation that cannot be waived simply by not seeing the child. If it were, the vast majority of non-custodial parents would simply stop paying, and there would be no point to having child support laws in the first place. The right to see the child CAN be waived, but he does not get to stop paying child support because he's made the decision not to have a relationship with his child. Note that the custodial parent does not have to force that right on him if your husband wasn't trying to see the kids, because it's not considered beneficial to the child to force parent and child to spend time together when neither of them wants to be there. It's up to the non-custodial parent to seek visitation (at which point, the custodial parent cannot interfere and must allow it).
However, children don't get to decide if they want to go to visitation. If your husband wants to see them, the mother MUST make them go. She's presumed, as the parent, to have some amount of control over her children (and if she can't, maybe she shouldn't have primary custody). She's in contempt of court if she doesn't, and he could file a Motion asking the judge to penalize her for not respecting the visitation order. If she's doing anything to try to alienate the kids against him, then he can ask that she be ordered to stop and penalized for that as well.
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