My prediction
I think that the culprit is zeenat, because 7 years back she might have married sahir because he was a rich family but then she must have always been negative about the things sahir can do (becoming one of the richest people in India). I think before her accident happened she must have done something that hurt sahir but he found out after zeenat a accident happened. I also think that zeenat did go into coma but couple years later she recovered but acted that she is in coma. Because must have thought that sahir must have moved on in his life so her acting like she is in coma would give a huge benefit of ruining sahirs life for betraying her and no one would even suspect that she did all of this and would come back into his life and take all of his property.
The things that r happening in niyamat house must be because of zeenat and KA must be involved so that no one suspects her either because she is kind of a money minded woman so when zeenat gets the property she would give some to KA and destroy everything in sahirs life.
Please leave ur comments on what u think might happen