I would not fork or re-release proprietary code. I would ask my LLM to write a very rigorous end to end test suite for your tool, delete all the code, then have a clean context LLM re-write the code to pass all the same tests. Then I could publish it under an open license.
Ads are a cancer, and it is a matter of weeks before someone does the above where you have zero recourse.
I suggest open sourcing the code properly without ads yourself before someone does it for you. If you do that someone might donate to you instead of paying for the tokens to clone your work.
Software is no longer a moat and DMCA means nothing anymore.