Ha, caveat emptor. Oh, wait, OP isn’t even a buyer and paid nothing for the code and blindly built it into the app. No reading, no understanding, just copying. OG plug-in author has a problem with people abusing license key system, builds in code to detect it. Disclaims it vaguely, OP gets bitten and has the gall to call it stealing. Author offers to help OP out, OP puts him on blast. Zero sympathy, even at 30%.
There is a huge divide between "oh hey you didn't read the license and missed the fact that this OS addon takes 2%" and "the license said 2%, but it's actually 30%, oops my friend!"
Op called 2% stealing, 30% is for basically triggering the anti cheat. OP should have paid paid the license and read the rules.