I'd guess that getting this question "correct" almost requires having been trained to parse the problem in a certain formal way — namely, purely in terms of propositional logic.

To get the question correct you just need to consider the falsity of the premises. You don't neccesarily have to parse the problem in a fromal way, although that would help.

On this reading, Ace is most probable.

Ace is not more probable. It is imposible to have an ace in the dealt hand due to the requiement that only one of the premises is true. The basic idea is that one of the premises must be false which means that an ace is impossible. It is impossible because if an ace is in the dealt hand, then this means that both premises are true which violates the requirement (Exactly one of these statements is true). I have explained this further in this post

I updated the first example to one that is similar to the one above by Tyrrell_McAllister. Can you please let me know if it solves the issues you had with the original example.

That does look better! Though since I can't look at it with fresh eyes, I can't say how I'd interpret it if I were to see it for the first time now.