A cable can do all kinds of bends and curves and the tension stays the same (less friction losses). Take a look here if you don't believe me. The angle gamma does not matter. The cable tension in your first diagram is incorrect; it will be the same as shown in your second diagram. Actually the only difference between the two diagrams is that gamma is fixed. If the first diagram were correct, the same calculation would apply in the second.

What does matter is the angle at which the cable exterts force on the arm of the cantilever.