Accidentally provided false information

I accidentally claimed on my coalition app that my quiz bowl team placed 7th in the state tournament when in reality we placed 8th, would contacting the college in question to correct this run the risk of them throwing out my application?

Seriously doubt it. Your team did not place 2nd, and then had tou claim first place - a decisively different matter.

There is no difference in the placement that far out from the winning place.

However, if others from your team are applying, and that team is school-specific ( pretty sure it is), the discrepancy * may* be noticed.

I really would not urge my kid to correct that error alone, though I would tell to correct it as part of other (new) information submitted.

Agree. Correct as part of updating on grades or changes in classes or such

I wouldn’t waste their time with an update. It will not even be a moment of their time during your file review.