Because the sisters told to! He couldn't answer to ED why he thought Rhea siphoned that money! Then his video of fake-acting and crying that Rhea poisoned his son which was so conveniently released right after that chat leaked!
How can people NOT see through their lies and drama?
How could he possibly know what Rhea was doing in Mumbai when he was in Patna at the time of death????? That itself shows that they had an a vengeful agenda aganist Rhea from the start. Of course, Rhea is no angel. She also said so many lies and dumb lies too. At the end, it seems everyone just cared only about his money and not about him. And that pushed his already broken psyche to the edge.
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