My take on what the joker is doing !!

Ya, since the joker is Yash.. I feel what he is trying to do is either make Sid mentally unstable or prove that he has gone mad infront of the family He is just scaring Sid in all possible way and Yash very well know Sid's bad habit is hiding and he will keep the stress all to himself and do idiotic things which will make ppl believe something is wrong with Sid

I don't see him harming anyone esp Roshni but its just scaring and suffocating Sid.. Now he may even blackmail Sid of killing alex.. So, Yash is playing a very calculated game knowing Sid well..

The only person who can flop the game is either Roshni or DD.. that too if they find Sid's behaviour suspicious and force him to say the truth like during Raghu track😕 Or else I see some tragic ending of this track

Already he s damn scared ...uff..I can't see sid like this.roshni has to support sid