In one episode Meethi said she was pregnant... but we don't know how she lost the baby... we also know how Adi treats her... kids kaise honge... 😆 vaise bahar itna time pass karta hai... may be ho jaye...😆 anyway we can't guess about the promise right now... may be he just promised to stay away from shekhawat family... & nimmo fears if he got attached to his wife... they'll start demanding their share from the property...
I think maybe rp or some else had a hand in meethi loosing the baby so the shekhawat family doesn't have any heir.