It makes no sense. It only reinforces the fact that Priyanka cared about her brother, by monitoring his monetary transactions. And here toh she caught someone red-handed doing some transaction without Sushant's knowledge, so she'll obviously be pissed.
Sushant himself literally says, "Aakhir mujhe jaan na hai ki usne aisa kyun kiya?"
Now question: when exactly was that? And how did Rhea get her hands on this video?
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