Use an aim offset.
And camera forward vector normalized, broken, take y.
From that, the value is always in a 0 to 1 range.
So your AO can probably use 0 and 1 directly.
That’s assuming you want 180deg.
Neg numbers should be the back/opposite of what you need.
Its possible that the front is actually in a different range depending on what you get the forward vector of.
If it gives you - values on the left and positive to the right, just set your AO to -.5 .5 range - instead of doing math.
(You could add .5, and then always have a value from 0 to 1. But its a needless expense).
Also,
The abimation blueprint is not supposed to have any code.
Do everything from the characterBP.