Education

The TurboTax support FAQ you viewed has the correct information - https://ttlc.intuit.com/questions/1900511-can-the-cost-of-private-schooling-be-deducted

The funds from the 529 can be used for grades K-12 but they are not deductible on a federal tax return.  Only post-secondary education expenses are deductible on a federal tax return.