GTA IV ZLIB 20 Fatal Error

Hi there, i've used my disc version of the game to quite frankly dodge the stupid 'update' (downgrade) on steam. In spite of this, i figured i'd play around for a few and get the nostalgic run from the gta iv police while being on islands you're not supposed to have access to early game. Well, after probably 20-30 minutes of gameplay, i get this error that i've quite frankly never seen before. Zlib 20 Fatal. After some searching about, i've noticed this tends to be connected to pirated versions of the game - which i know is not true because i purchased this game from Walmart many many years ago. So how would i go about diagnosing this issue? The only things i did 'weirdly' was set the date of my PC to 2014 so the SecuROM bs would verify, then back to 2020, and i've popped xliveless.dll in the game file aswell. Other than these two things, the game is installed as any other average user would have it. (vanilla)

Thank you for any input, and have a good rest of your day. 

-Phantom