Aparna, if we are talking about general scenario or general interaction at work place, I would agree with your above post a 100%. It is because many good and simple people get trapped easily, particularly when sob stories are told. And I agree, it is hard to shove off someone just like that, due to which the good person may fall into a trap.
However in Shiv-Rasika's case my opinion is different. This time Shiv looks out of character. This is because he always had empathy/sympathy for everyone, but at the same time he has also been sharp enough to judge the other person. For example Heth Singh or Jagya. So him not being able to judge Rasika or being stern with her is not digestible to me.
On the other hand Rasika's character is so OTT and obvious. So it becomes all the more unconvincing to see that the smart brains of Shiv did not consider what is the acceptable standard behaviour in treating a female subordinate. After all she is not his friend, girl-friend and he does not have any vested interest in her unlike when he was dealing with other women like Ashima , Anandi or Saanchi.
So yes, it is a good track and if court case is handled well it will be interesting to watch. But the current scenario could have been handled by CVS in a subtle way. They need not make Rasika too loud. It is because she was so loud and obvious, Shiv comes across as naive, which is opposite to his character traits shown so far.