From vansh expression I felt he is genuinely concerned and worried for her , hee do cares voh uske chehre se pata lag raha hai , I don't think that expression was of love or like , it genuinely showed worry, concern and need to help and protect 😕. So I guess vansh knows ragini ke sath kuch bhot bura hua tha and he wants to find out the culprit through her .