He's great, but I honestly want to know how in Hell beneath the writers managed to pass him off as not being the Joker.

It's like how Wolfenstein tried to hide the fact that the main antagonists were the Nazis by replacing the swastikas with W's and calling them "the Regime" for the German release. Like, it's very clear what you're trying to get across. You just changed the name and appearance.

He's cool

While not the actual Joker, he serverved as a great villain for the show and even made an impact on his brother, the real Joker

I liked him way more than his brother. They really screwed up by killing off Jerome. One reason why I stopped watching.