I do not know if I will be coherent in my thoughts. After more than 12 hours of watching that shocker of an episode yesterday I am still not in a great frame of mind to think coolly and rationally. But let me put down what I thought for whatever it is worth.
A woman who looks like Prachi is shown residing with the Dasguptas (who by the way I did not like) and is apparently married to Proteek, the eldest son of the family.
If it is Prachi indeed, why would she marry anyone when she is still legally Milsi's wife and more importantly is supposed to love him to death? After racking my brains, here is what I think could have happened. After the blast,all three would have been injured. Maybe Prachi was more injured than Panchi. Seeing this, Proteek (the less injured of the three) may have stepped in and saved Prachi. In doing so he may have left Panchi who ended up dying (maybe a ball of fire consumed her). So Prachi feels both guilty and grateful to Proteek. Guilty because in saving her, he lost his wife . Grateful because without him she would have died and more importantly the symbol of Michi love, the baby, would have been wiped forever. So out of these feelings, she may have agreed to stay back with the Dasguptas and act as his wife and take care of his son. I don't think they have anything other than a platonic relationship. Not only does Prachi love Milsi, by the looks of it Proteek too has not forgotten his love for his wife.
Granted that I did not like the familiarity displayed by both, especially Chi, but then this is one of the instances when Chi disappointed me, the other occassion being her refusal to tell the truth about Ritwik at the beach even after seeing him in the broken state and even after Suki herself told her to reveal the truth. I still like to believe Milsi is the only one in her heart. I am not condoning her behaviour but I'll wait to see what they are really planning to show before drawing my conclusions on it.
If this woman is not Prachi and is Panchi ('Face Off' theory), then I do not think Prachi is somewhere in coma but may also be residing with the Dasguptas. I get this feeling seeing baby Michi (I think his name is Sunando). The boy has long curly locks. If Prachi had delivered him in the coma state and Panchi and Proteek are taking care of him I don't find an explanation for the long hair. If Prachi was around either as playing the role of Mrs. Dasgupta or as Panchi's sister, then she may have kept this style for her son for she wanted to be constantly reminded of Milind.
Now why did they not show an interaction between Prachi and her son if she was really Prachi? I wouldn't put too much weight on this and draw my conclusions based on it because this show has never given much sensitivity when it comes to children. The way the Ritwik issue was handled was testimony to that fact. He was mostly a neglected child in the Shah household.
So at the end of the day both possibilities still hold. This may be Prachi acting as some else's wife for the reasons I mentioned or this could be Panchi but Prachi is alive and well with the Dasguptas. If the latter is the case, maybe she will be shown on Monday.