I would suggest not casting to the bot. Select the bot actor in your content browser and give him an actor tag “bot” and then on the overlap check if actor has the tag.
Have you player use the actor tag player and then no casts are needed.
Edit: fixed up ui reference to not be time dependant
Hud reference init
Inside of your hud class create the widget
Remember to add the proper tags to the actors
I’m guessing the bot is supposed to be possessed by the player to activate / deactivate these widgets?
Edit: this will work only for standalone games though as the trigger lives on the server in mp games and can’t access the player hud then. You would need more complex logic then.