You still don't need to amend. We're seeing this frequently (it happened to me, personally). Apparently, the IRS has created a problem by not having a form to report the situation where the taxpayer uses all the 529 plan distribution for qualified expenses, because nothing about the 1099-Q went anywhere on the actual IRS forms.
You should reply to the IRS that it was all used for qualified education expenses. I attached a copy of my billing statement from the school and a copy of TurboTax's 1099-Q work sheet. That took care of it (2-1/2 months later).
At least two users have reported receiving a CP2000 letter, from the IRS, on 529 distributions. They replied that their child was in college and the distributions were for qualified expenses, which they listed, but they did not provide receipts.. They later received a notices saying they were in the clear.
