Final riddle game breaking glitch

[SlurpCoin Alpha Male]

I'm on the riddler mission with 242/243 solved except the collar one in the orphanage and cat woman left so I can't solve it! Please help

[JonoAMano]

It is not game breaking. Remember the last thing Catwoman did before leaving the Final Exam room with Batman? Scan where she threw the necklace and you're good to go.
http://steamcommunity.com/sharedfiles/filedetails/?id=858767536

[MASTAN]

I don't remember scanning it after Catwoman left. Maybe got it accidentally when scanning room while it was still on her.

[JonoAMano]

I always scan it on her after the first robot fight in the Orphanage.

[Laura Rules Me]

You can find it in the last riddle room where she threw it away?

[S!nker]

Yeah it's i the floor somewhere. I did the same thing as you. just zoo in an try to locate it, won't take too long

[JonoAMano]

Click on the image I posted above and read the caption; you'll see it.

[wcubowman78]

Yea I've found the collar and tried scanning it and nothing....and no I haven't completed it yet