We have been battling our insurance for coverage for Behavior Parent Training for a couple years. All of the research is clear that giving parents extra skills is one of the most effective strategies to supporting kids with ADHD. WE haven’t been able to access it yet, but are on a wait list and have been reading Taking Charge of ADHD which is what the most effective programs are based on. There is actually an incredible clinic directed by the author. https://www.cincinnatichildrens.org/service/c/adhd/services
Hope that helps and that you are getting the support you need.