Posted:
Shyam got the signed papers well ahead of time before reaching airport. And he had plenty of time to pull the strings because he anticipated Khushi will hold of Arnav at any cost till last moment.
Now Shyam plan would be to fake Arnav's death. So, now the clever lawyer has to prove to the court that Arnav has died. I think he will kidnap Arnav and create evidences to prove Arnav might have died. After some cooling period, court will allow execution of Will if there is sufficient evidence of death / missing persons.
Although, it seems Shyam is not behind, I am most certain he is using his underground connections to take out Arnav.
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