Based on the number of divorced couples I have worked with over the past 32 years, I would say that your chances of having this reduced are very slim. My own divorce is a good example. Due to a number of factors including the loss of a major client that was purchased by a larger company, my income was down in 2005 when I was divorced. Her attorney believed that I was "sandbagging" and keeping my income low, so they calculated a much higher income for me. I had another large client go out of business (found it more profitable to sell the assets and live off the investment). So I was below what they "expected" for many years. I went back to court on three occasions to get it reduced, and was unsuccessful. The only good thing was she tried twice to get it increased and was not successful either.
I had a client who had cancer and became unemployed as she was unable to work. She did not have disability insurance, and yet the court would not reduce her child support obligation. As she was unable to make the payments, she had her driver's license suspended, and is on the "deadbeat" list. All for a condition she did not ask for. She is now Stage 4, and has literally months to live, and is totally unable to work. Yet the courts will not let her out of her obligation.
A former coworker had three kids, and was paying child support to his ex. She was convicted of selling and using heroin, and felony child endangerment. The kids were taken from her when she went to prison, and my coworker had physical possession of the kids. She got out after more than 10 years, and sued for back child support, and WON! She did not have the kids, but since he never went back to court to get his obligation set aside (he would have won, because she was in prison and could not contest it) the support order never stopped.
The divorce courts have unfortunately seen so much fraud and manipulation that they are unwilling to make decisions even when it is warranted. When I worked in the tax department of a large corporation, one of the officers wanted to get his bonus (huge) paid through an offshore subsidiary so it would not be reported on his W-2 so he did not have to give part of it to his ex-wife. I refused to allow it. And I am sure that this was not the only case of manipulation that has happened.
I wish you luck, but you asked for an opinion, and I gave you one.
Have a great weekend!