First when Rashi was being accused, Hetal had a blank face, like she does most of the time when Gopi is being blamed or screamed at. She basically is listening and helpless.
Her Second major expression was when Koki says "that Rashi was suppose to stay back to clean up the spilled juice, and if the juice wasn't cleaned up then what was she doing in the kitchen".....At that time Hetal closes her eyes in pain..........because it proves that what Koki is saying is true.
Her third major expression was when Rashi says "you don't want to believe me but ek NAUKRANI's words you want to trust"............Hetal whips her head towards Rashi as she can't believe that Rashi just call their loyal worker who they consider a part of the family, Mani, nothing but a Naukrani.
Her fourth major expression was when Koki makes her final judgment and asks Rashi to leave the house as her punishment. Rashi goes to Hetal but Hetal only turns her face the other way.
I think all these expression for me come to one conclusion, that Hetal knows Rashi is guilty and is in shock that Rashi can go down to such a level. She indeed does try to explain to Koki to not give such a huge punishment, but that is Hetal's nature to being with........
Rashi is more then capable to instigate Koki and Hetal but here I think Hetal knows that Rashi is lieing......although she doesn't want to give a huge punishment.......she can not say anything as she knows she is wrong. She proves this by stating that "pyar se be samjaya ja sak tha hai" You can bring a person on the right road by love also. This at least state that she knows Rashi is on the wrong road.