It's true that your remarriage effectively vacates your divorce judgment and pre-remarriage court orders.  As of right now, there is effectively joint legal custody, as married parents.

However, he can't prevent you from moving out, with the children, and he can't even get a court order in California yet, because you haven't been there for six months, which is required to make it the children's home state under the law.  You can go back to Nevada and get a court order there, as soon as you arrive, giving you custody, and perhaps child support as well.

You'll have to re-establish residency in Nevada, for the divorce, but you can start the custody and child support case right away.