Ex wife refused to relinquish custody of son this weekend.

A little back story. We’ve been divorced nearly 3 years at this point. In our parenting plan she was given a provision in the plan to request a UA should she suspect any illicit drug use ( definitely should have outlined some clear criteria in hindsight, as well as put 100% of the cost on her). After I had a very brief relapse after she blindsided me with an ex parte full of hyperbole, conjecture, hypocrisy and all other manner of weaponizing the family court system. This provision had a two year cap on it and has expired as of September. I tested a handful of times, all negative and all accepted by her at the time. Well, this Friday during a zoom call for parent/teacher conferences my eyes dried out the worst kind of way and was just struggling to keep them lubricated. After it wrapped up I got a call from my mom saying my ex had called her and expressed concerns that I was using. Again, eyes were so very dry, it was a zoom call, in what I can only describe as inadequate lighting to come to such an assertion. She called me the next day (I just didn’t have the energy to do this song and dance day of). She said I needed to go UA before I could see my son. I said, that provision no longer applies and refusal to relinquish custody is in breach of our parenting plan. Hell, I even said she can drop off and pick up and my mom and step dad will be over to “supervise” to put you at ease. Even with totally reasonable compromise she refused. Now she states she’s going to file a motion to have UA reinstated and she’s going to retroactively deny UAs I passed from as long as two years ago that she was fine with at the time and everything just resumed as normal afterwards. Am I missing something here or is she actually out of her mind thinking that a judge won’t immediately toss her motion out and possibly approve some of the modifications that I now am wanting to make? Thanks in advance fellas.