Everyone knows that Tulsi will be alive soemwhere...and where ever she is she must have ehard about the bus accident. She should be knowing that people in Shantiniketan are thinking that she is dead in the accident and then everyone accused Mihir for this. As she loves Mihir and even prayed to god that "Mihir ke sare dhukh mijhe dena", she should get in touch with atleast Karan to inform that she is still alive.
For another 20 years if everyone is in the impression that Tulsi is dead...then it is going to be bad on Tulsi's part...rather Ekta's part for not showing concern towards karan...all bahus...BA, Gautam.
Kyunki is habituated to show what is needed to the story without anyother logic.