I am sure that Madhuri is a planted one. My view is also that she can be mithali the mother of riddhi. If I am not wrong sarthak hasn't seen Madhuri only heard about her. Mithali can be the long lost sister of Madhuri may be. It can also be like she lost her memmory . Maybe malhar ki Jo bhi dushman he usko wife as di said above.. may be both thinks that their daughter rwas killed by malhar by mistake one lost sense and other is our for revenge. The person may be utilizing her similarity with Madhuri to extract revenge.
Titu di atharva possible he. But he has no professional angle the one who is troubling malhar is the head of naxal gang.and for all theses activities funding is must as of now atharva has no resources no wealth no contacts neither support( and he was in assylum so no way that he get contact with them)to exclecute a master rplan like this and as of now he will be safe until or unless he is a kid. He won't come out from the safe zone unless he get something strong to take over kalmw