My favourite part of writing the LSAT is no longer dreaming about playing logic games. I'd take a reading comp on art history any day over one of those dreams!

I think that you've translated it really well!! I can only see one error in your reasoning for answer B to be correct. While you were correct to look for 'not evidence' as the necessary condition, 'not in mind' is actually the logical opposite of the sufficiency condition you're looking for in the correct answer. I'll try and phrase that differently. The stimulus states that Einstein's probable knowledge of a phenomenon (P Advance) is sufficient to draw the conclusion that the P advance should not count as support for that theory. In your logical notation, this would look like: mind → NOT(Evidence). That is the answer you're looking for. You're on the right track though!!!

I originally chose A, and even blind reviewed that answer. I can see now why it's wrong- the stimulus' conclusion makes no comment on the truth value of the statements told to participants in the study. I can't believe I missed that!