My conclusion is yes, Myrah knows Rudra a little bit more than we the Forum people think. Although it has not be shown, but it can be concluded from Friday's episode when Myrah tells Rohit to take it easy on Rudra as "he has gone through a lot in his life".
I would think Myrah has been having long conversations with Maithili and has been getting inside information! At least this is what I would like to believe. So yes, Myrah knows Rudra a lot more than what is shown.
Time constrain, guys. Now many things we just have to play it in our heads.