Multiple actors with one player controller.

I am making a turn based tactical rpg game where there will be several controller characters on screen at once. The player would be able to choose which character to command (move/attack/items/etc). I am using a player controller “pupetting” all the actors and the actors each have their own blueprint. There are several variables stored in each actor such as health, stamina, movement speed…Right now, I am accessing those variable from my controller via “Cast to” node. But the problem is, I can only cast to one character which has player index 0. Any other actors cannot be called by the node, even if i change the player index to 1, -1, etc. How do I solve this issue?