I agree with Mon-El
The reason why I agree with Mon-El isn’t because I love him and Kara together. The reason I believe him it’s because from what I’ve learned from every book, TV show, and fanfiction out there is anyone that comes back after being with the enemy most times they end up working for the enemy. For example the 100 when the Grounders returned Murphy they returned him so that he could kill off the 100. Another example is when district 13 got Peeta back so easily and it turned out he was hijacked, oh another example Terra from Teen Titans so people should listen to him.