He is not in the books he is an original character

Bandon doesnt see the future he sees a possibility of someone's death according to the show and amberle also doesnt see the future. When she touches the elcrys it communicates with her by showing her warnings of the tree dying and what is to come if it dies.

Bandon is not a character from the books he is adapted for the series so i have no idea what his overall role is or if he is even going to have any other role besides preventing wil from leaving and saving the handmaiden lol.