All this reminds me of Yeh Hai Mohabbatein, not sure if you guys have seen it. It used to be my favorite show before the time slot changed and especially before the leap when it was all shot to hell.
In that show too, the ML (Raman) and vamp (his ex Shagun) conspired behind FL's (Ishita's) back to make the ex a surrogate without FL's permission. And then once the baby (Pihu) is born, shit happens causing the ML to be very nasty towards FL. FL is presumed dead, and ML and vamp are left with the baby.
The vamp has made a 180 degree turn from evil to miss goody two shoes, and ML and vamp are faking a marriage to raise the surrogacy baby (FL's biological child). No memories of FL in the house at all. Vamp is even wearing fake sindhoor and magalsutra. Even there they had a full family of people to help. Still they faked a marriage.
Unfortunately, GHKKPM is a hundred times worse and crass than YHM. I can totally see them going this way. V and PP faking marriage for Vinu.