Riddhima basically will lose the document. Like she lost shera and the chip. She will continued get preparing. Mehendi Haldi celebrate vi honge. Then she will get ready for marriage and finally get access the paper. It will b the wee hours of the marriage. She will b shocked but will eventually got married. Vansh was genuinely smiling. I dont think its a smirk or anything. Then a heart broken Riddhima will try to commit suicide or she will express her devastation in that bathtub scn.
Or....She will know nor Vansh her parents were real culprits.but i think even if its true she will got to know about this later.