Ask your attorney and suggest that he should do the work to get you that, because he screwed up.
My name is Stephen R. Cohen and have practiced since 1974. I practice in Los Angeles and Orange County, CA. These answers do not create an attorney client relationship. My answers may offend I believe in telling the truth, I use common sense as well as the law. Other state's laws may differ.. There are a lot of really good attorneys on this site, I will do limited appearances which are preparation of court documents it is , less expensive. However generally I believe an attorney is better than none.
Seems like a nonexistent, ex post facto law. The Court should retain jurisdiction to divide that which was forgotten if the Court had jurisdiction over them in the first place.
The Legislature is always passing new laws, and I won't even allege that I know all of them. Nevertheless, I am inclined to agree with attorney Burns that the law you describe, spinging forth liability where it did not exist before, may not exist, and certainly has the feel of an ex post fact law. The existing law does have a procedure to recover un - reimbursed health care costs when there is already a support order in effect, and your current attorney should be able to make that request of the Court.
As stated above -- I have NOT actually stated any legal opinion, because I need to know more before I can start to form one.