I don't particulary fancy the theory of a mechanical offset because of loose bolt (slipping shaft). People do know how to manufacture square shafts and splines and keyed shafts and safety wire and plenty of other tricks. I don't know how much is one of those vane things, but no less than 3000 dollars for sure. Probably way way more. two cilindrical shafts with a screw tightening one aginst the other is not a proper way to do the job of critical torque transmission without slipping (well, maybe in toys).
In other words, I would not expect any connecting part of a rotary sensor with an all round shaft. Proper way: Splined (if it needs adjusting), keyed, or at least with a D shape.
Also, a mechanical offset does not explain the previous electric gremlins. (FEEL DIFF PRESS, SMYD computer failures and others).