I have a feeling they are good friends. They are Bengali, worked together, have a common language & family friends there is no reason to hate each other. Whatever news in the media or Sreejita's byte looks like PR propaganda especially on part of Sreejita. Tina is surely a bigger star & Sreejita sold the rivalry theory to get into the show.
I think Bigg Boss team got the juice & that's the reason they cut Sreejita's performance in edit & also called them in the confession room to clarify. Sreejita's journey doesn't look rosey infuture if she actually played with the makers.