It's an Ontatio E test

I know it failed CO2 emission. The limit is 1... and my car got a whopping 4.28.

They basically said my exhaust is bad and I gotta fix it for them to continue diagnostics. As well as replacing the oxygen sensor.

I really don't mind replacing the Cat/con, I just want to know if I can use a universal one instead of the $700 Mercedes Benz ones.