Kirthi dear as always you have come up with the deep insight on the
situation analysis.
Yup though Aarti saved him as she was always suspicious of Ishita and had watched her advances on Yash.
But also as you said, Yash would have been emotionally damaged if this would have gone through. As we saw earlier how emotionly damaged he was after Arpita's death. And on top of that he did not believe Aarti when she was trying to prove her point right about she got the call regarding Yash's accident and she saw some one in the house who looked like kidnapper. So his guilt would have been huge burden.
This also brings another thing in my mind that the way Yash reacted to Ishita's exploitation about the news of Aayu the same way Aarti responded to the news of Yash's accident.
But above all the performance of the actors was superb. and love those Kantaaps. was waiting for that..