Muskie,yaha samajhnewali bat hai....Why Vansh jumped?
For Riddhima,he jumped he showed him what extent he will go for love....but do u remember he said -"Dont worry Mom mein bohut jald wapas aunga... This indirectly was for the world that no one can defeat him in an unfair game.He is not a fool,he knows his enemies are lurking around his family. He will have to protect them.
How can he die without knowing
Who killed Uma? Why Ragini was killed?
He knew that Siya was presumably hurt by Riddhima (I know its a lie) but Vansh will punish the culprit. (As of now riddhima later the real one) So he will return to give an answer to the betrayal and protect his family.
Kabir wanted to show him in a bad light that he was trying to escape and he encountered him.This would have given Kabir immense pleasure . But Vansh will neve let him to enjoy that. He knew Kabir legally will never b able to punish him so he apprehended that he might kill him...So he must have informed Aangre to plan a back up. Now we know Vansh is an under water swimmer (He did a stunt in Cruise). So he jumped off the cliff and manage his fall and then he must have swam and hide himself in a hide out or somehow managed it. (They will show how he did it later) Then he arranged a dead body of a same height and make him wear his clothes..He put fire on that body....Now he will fabricate his death and that will b interesting to watch how he return.