There isn’t anything unreliable about casting in UE4 and I see a lot of devs making this mistake on this forum. The “Cast to” node is actually a thing in programming called “Type Casting” or “Type Conversion”, you can look it up for clarification on what it’s definition is. Here is an example of how it’s used in UE4 blueprints:
[Get Player Pawn] -> [Cast To “CustomPlayerBlueprint”] -> [DoPlayerEventOrGetPlayerProperty]
You see, the Cast To node changes the type (Or it’s class) from the Get Player Pawn reference to CustomPlayerBlueprint because CustomPlayerBlueprint is a child actor of pawn.h. If CustomPLayerBlueprint is NOT a child of Pawn than the cast will always fail. Maybe the UE devs could look into making a note or something in the future for the cast to node to explain it’s function a little better.
Edit:
In your situation I see [Get Player Character] and a cast to SheilaTheFox. Let me ask you this one question: Is SheilaTheFox parent class Character.h? I’m guessing it’s not? Good luck 