A lot of the others are better at domestic relationship orders than I but in most orders and contracts, there is such thing as 3rd party beneficiaries rights. I suspect since she was named as a beneficiary of the order, she could seek an action on her own if her rights are infringed.
I suspect it would result in a re-write of the order removing those rights and since she is not actually a party to the situation, she would have no standing to seek reinstatement but, until then, she should be able to argue her rights under the order without the husband.
Without the complete order, it is difficult to ascertain just what rights SM actually has though. It may end up they are only ancillary benefits and as such, would have no right to sue to demand her rights and be more like your situation.
The major difference is SM was included by name though and given specific rights. Take note though that those rights are extremely limited. What is posted is merely showing a right to be given some information concerning the child. Along with that, when it spoke to medical and educational decisions, it spoke only to "the parties", which, unless SM was included as such, does not extend those rights mentioned to SM.