A while back she said she didn't have a case against him but I keep telling my husband to go down & inform the child support about it so he can pay the right way, can she get in trouble or just my husband?
Yes. All money given needs to be reported.
If there is no legal documentation stating how much he should be paying and when it should be paid, then he's currently at risk of her going to child support and asking for back pay. He should go to the child support office himself and open the case himself. It looks better if he initiated the paperwork.
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