Those veneers are tricky, man. Over sanding is the easiest mistake to make. What worked for me after doing the exact same thing was to stop sanding by hand that day and just let it sit. Came back the next day and used a card scraper instead of the orbital on the curved spots. Also started keeping my stain cans in a plastic tray with a lip around it after I tipped one over. Took me a whole day to clean up that mess from the garage floor. Sticky concrete is no joke.

Buddy of mine had his Crain crack near the foot end same way.

Oh man, that is the most accurate thing I've read all day. My niece did the exact same thing with Splendor - completely ignored the whole 'collect gems and buy cards to get prestige points' thing and just started hoarding all the red chips because 'they look like strawberries.' She spent the whole game making me 'buy' her imaginary strawberry lemonade with them. Kids have this amazing ability to look at any set of rules and go 'nah, here's what we're ACTUALLY doing now.' I think they can smell when a game is trying to teach them something and they'd rather just have fun on their own terms. Your nephew turning grapes into imaginary snacks sounds way more engaging than actual Viticulture anyway, honestly.