While the official may not have spoken, I think it's a safe bet that the AJC reporter interviewed either coaches/AD or players to get the official explanation of the ejection. On the other hand, I know nothing of the AJC and their journalistic integrity. I would hope they fact check their stories and use multiple sources before going to press. On the other hand, maybe journalism has gone out the door as in so many other places.
Reading the comments on the original AJC story provides some context, though it all has to be taken with a very large grain of salt.
If I did this properly this link is to the AJC story and not the Yahoo report that was linked previously.
Milton coach miffed over Mann’s ejection; Georgia signee can’t play in semifinals for final | Prep Zone: High School Sports