Your theory is not crazy at all in fact I can see it very much happening as a back story. :)
owwh yeah..i feel there's a lot of things to unfold in this story! especially whn it comes to Harshad n fab5 connection. The main thing we want to know is the reason behing Harshad dumping Mukti, was it coz he was done with her? or whether she did something which left him hating and made him against fab5!
we noticed how protective and defensive Mukti gets when it comes to Fab5 so maybe Harshad said something or did something to fab5 resulting in Mukti's outburst and then she had to choose maybe one of them n she went for Fab5!! making harshad against them even more.
Just is just a crazy theory!!!