Good analysis, Matt. Where the gudgeon got bumped we will never know for certain, but I suspect you are right on track. It's not something that is really noticeable and you would never know it was damaged until you had the boat in the water and tried it out.
The top of the gudgeon only needs to move about a 1/4 inch to bring it straight (see photo below). While I did attempt to twist the gudgeon straight with the screws loosened, I only twisted it with my hands and did not place a lot of pressure on it.
My first choice would be to straighten the gudgeon, if possible, rather than compensating for the cooked gudgeon with rudder adjustments.
What I don't know is what type of material the brass inserts are molded into and whether or not it is practical to replace that "block of material" with a new one including new brass inserts. If that is not possible, how about this? - I remove the rudder and gudgeon, see if I can straighten the brass insert and fill any gaps made by the unwanted "twist" with epoxy to stabilize it. Then re-install the gudgeon with the original screw.
If this doesn't work and as a worst case scenario, I could fill the hole and damaged area with epoxy, drill a new hole all the way through the block of material and through the Oasis hull, insert a new (longer) bolt through the hole and place a locking nut on the inside of the hull (with appropriate sealing washers, of course).
I'll be interested in your thoughts. Thanks for all your advice and help