Here is what I think should happen, I truly hope CVs listen this out.
Arhi have already proved their partnership works wonders, example Payash engagement.
Now, ASR notes KKG's utter discomfort when she is introduced to Shyam and leaves the house in a hurry. ASR notes she is disturbed. When KKG is forced yet again to show up at RM for her sister's engagement preparations, ASR notes her engagement ring is missing and she is evading questions about her fiance and her own engagement.
ASR corners her and questions her. KKG bursts out that yes her engagement is broken and that what will he do anyway because he has to worry about his own family and relationships. That will trigger a thought in him. Further disturbing interactions between Shyam and KKG will seal ASR's suspicion and he will put two and two together.
Again, he will corner KKG and ask her and she will confess. Then she will remind him that the matter should be handled delicately because of Anjali's vulnerability.
They will partner to reveal Shyam. ASR will try the power and paisa angle, KKG will try the relationship and emotions angle.