All solutions are from my playthrough and experiences may change, if your playthrough does not match comment why and I will edit
*** Spoiler - click to reveal ***
Starting off the chapter Batman will fall through GCPD and have a rebar stuck inside him
The person you saved will help you, you will black out from blood loss
You will wake up in the Batman, to a dad joke...lovely
Dialog, Tiffany is also there
Examine all of the nodes on the batcomputer table, Tiffany makes an entrance
You will choose if Tiffany comes with you, or helps from afar
Show up at the crime scene, and pick up evidence you see, and scan objects with the drone. Go up the stairs and look at the water tower until you see the Jokerang in the water tower.
Story will progress
Harley Quinn will show up, a few QTE's. A short fight sequence with Harley Quinn will initiate
Arrive at ACE chemicals, dialog, QTE section, plot twist
Agency arrives, FATALITY , Long QTE section
You will have a choice to call Joker your friend, or never
Long Chapter end