I think CC will go there to basically plant more evidence against Bon for when her truth will be revealed so that they'll go against her more and believe she's a spy.
Das family isn't there, so I doubt Bon's exposure will happen there. It'll happen next day at Talwarbaazi.
About Bon telling Ani -- she is in a Bengali saree, and whenever she has worn this saree in the show it symbolized truth. So it's very likely she will either tell him then and there or the same night in the yellow reel outfits. She might ask him to meet her in the same place they had gone to during their date and meet him as Bon.