I'm disappointed in the second Harley, as well. I'm a Harley fan. Even the New 52 version. But it's so rare to see the original Harley anymore that it made her showing up like she did decently unique. And now that's gone.
As for the accent? They're basing her off a character from the tv series. And she really did have a horrid, generic accent.
The Harley 2 content is gotten by going to your lab and seeing a scene with her. Then heading to the sorceress a day or two later.
The Audrey 2 content takes a while. Just keep visitng the office of Lexcorp every day until Savage sends you an invitation to the wedding. Then wait some more until you go there.