Gary clearly said that Seerat doesn't know anything about the Sunny Sood plan so why would that be relevant to what Sahiba is telling Angad. Their focus is figuring out why Gary wants revenge, what his plan is and who his boss is. How would she realize that the 2 second mention of Seerat bringing something from locker may be significant. And she may not have heard everything said when Gary was in front of the car and only got bits and pieces of it.
