During a mission Batman gets de-aged, keeping his memories but having a hard time keeping track of them, and kidnapped by the leader of a trafficking scheme who'd just barely gotten away when Batman shut down the rest of his group. The only way to get to Batman is with an invite, as he plans to make Batman pay for ruining his plans.
Que Batkids showing up to try to win the bidding and rescue their friend.
Red Hood is waiting on Dick's request, having been promised that Batman would get rescued and then he could shut this entire thing down as violently as he wants.
Tim had needed some backing his other ID's dont have and had called Pru to help him rescue Batman (and also get him some LOA clothes) Damian had tracked down his old uniform and come as well. The two recognize each other and agree to pool resources to save Bruce.
Dick had found out about the auction when Deadpool had broke into his appartment and left a dufflebag with his old costume and an invite on his couch, apparently his respect for him extended to Batman. He'd gotten ready and Renegade had made his reappearance with a speech about how Batmna had 'stopped him from avenging his family and needed to get what he was owed'.
Small, emotionally distraught Bruce had taken one look at his son, thought Slade was forcing him to be Renegade again, and started crying partway through the speech.
Renegade wins just for that, and now Tim and Damian are trying to figure out how to get Bruce back from someone associated with Deathstroke.
(Jason gets a call from Barbara after he'd finished decimating the place, also assumes that Dick's plan had failed/Renegade had gotten to him first, and joins in on the chase.)
(Meanwhile until Red Hood shows up where Dick has hid them, Dick had no idea it was people he'd known chasing him. He's been trying to figure out what Ra's or a splinter group wants with tiny Bruce so badly)