I have a feeling we're being fooled by RS!
If she really wanted to end Surbhi track, she wouldn't have made her marriage public beforehand! Now, divorce is going to prove problematic! To get legal divorce, they need proof that marriage happened, and any search in that direction would reveal the fact that Harman is married to 2 (sisters) at the same time, which any legal court would find to be a punishable crime! Or, to avoid that, he'd have to announce that Saumya is kinnar, and he was duped, thus 1st marriage is by default void! But, that would mean separation from Saumya, which for Harman would be even worse than jail!
So, divorce would prove a complication...
Now, on the other hand, we see Harman trying to get Saumya to promise him that she'd never leave him, that she wouldn't sacrifice herself for the baby... BUT... she wouldn't give him that promise! Hinting that in the future, that's exactly what's gonna happen! Baby is gonna go missing somehow, and Saumya would go after it, most probably getting lost herself too in the process!
So..., where that would leave Harman? The wife he loves, would be lost to him! The wife he doesn't want, is stuck to him!
His uncle, is getting nasty, demanding his own son to be pronounced "waris" as long as Harman is not delivering a "real" one!
His parents, would probably be humiliated by chacha and chachi, for not having a real waris...
The "waris" issue would be turned from a mere "wish", to a "necessity" to protect his parents from his uncle's greed...
So, they're actually pushing things, in the direction we -naively-thought abandoned by CVs!!! But, it would seem that RS has not abandoned it at all! She's just postponing it a bit to appease us for a little while; and in the same time, making it more of a necessity than ever before! So that when Harman and Surbhi consummate their marriage eventually, they both seem completely blameless victims of impossible circumstances that no one can object to...