>the convo AR has with Roxy vs the convos Dirk has with Roxy
>the three way convo with AR, Roxy, and Dirk
>Both Roxy and Dirk saying outright that he's different
>the fact that he's been glasses and not a hormones having human for the past three years

there are a lot of ways prove he's different just by how he interacts with people vs how Dirk interacts with people when he's not actually pretending to be Dirk.