Medical expenses

In my divorce settlement, i agreed to provide health insurance for my child ,which is provided via my employer and i pay via payroll deduction.
The health plan specifies certain doctors, hospitals and pharmacies which are in the network.
I’am responsible for 75% of copay.
My ex-spouse used a non-network pharmacy for a non-formulary drug for my child,and is seeking
me to pay 75%, about 375.00.
if she had used a network pharmacy and had physician get authorization or change drug the cost would have been 35.00
My question is would i be responsible for medical drugs and procedures ,non-emergency if my ex-spouse doesnt use the
insurance benefits iam paying for , for my child

It depends on the language of the agreement or order. If she is required to stay in network you will have an easier time of this for sure, however even if there is no specific provision requiring her to stay in network, I believe the court may still come down on your side.