Part of course:
There May Be A Dark Reason Tyrion Made That Look In The 'Game Of Thrones' Finale (HuffingtonPost)
After Cersei (Lena Headey) initially walks away from the dragon pit meeting, Tyrion follows her to speak in private. During this meeting, Tyrion confesses that he never wanted to destroy his family despite all his talk about doing so. (And we were all like, “Come again, bruh?”)
Make no mistake, the fact that Tyrion doesn’t want to destroy the Lannisters is a major confession, and it could confirm that he will betray ― or has betrayed ― Dany.