something fun to think about is: does joker know that goro still remembers their true reality and he's willingly playing along?
it would parallel how joker knew something was up with goro before because of pancakes. so maybe it's like that. joker remembers and goro remembers. goro knows joker remembers and joker knows goro remembers. but goro doesn't know that joker knows he remembers.
like how joker knew about goro and vice versa but goro didn't know that joker knew (pancakes).
and i guess a question would be: why does goro need to pretend to be a good boy again when joker already accepted him for who he really was?
to pretend he was memory wiped and fit the role better? or because he genuinely doesn't believe he deserves friends as is so he prerends to be someone he thinks would deserve friends?