> It looks like OP's most recent post was deleted

Apologies, I had figured out what distinction you were getting at right after writing my reply, so didn't feel the need to keep my misunderstanding up. But thanks for the detailed explanation!

Edit: Actually, I'm confused again. To be clear, it sounded to me from the discussion in the Joe McCann video that there was no tweaking the answer to get the question, i.e. that doing anything other than verification in reverse would have been against their ethic, that the answer must truly follow the question for it not to be cheating. The integral is fixed in place, and then legitimately solved by a highly competent Reshetnikov who is good at this (and afforded plenty of time by scheming in advanced, as opposed to the illusion of only taking 3 hours), but too lazy to formalize their work or interested to see a 'clean' solution unbiased by their own approach to the problem. And then it's verified trivially using differentiation (something symbolic math software rarely fails at), as opposed to my original misunderstanding that there still would have been uncertainty. Right?