I have known about this flag for some time and the paper is in error. The C.A. Platt of Augusta is Charles A. Platt - not Mrs. Platt - and Charles, besides being captain of an Augusta militia company that tendered into the 5th Georgia Infantry, also ran a curtain business with his brother Jacob - and both were flag makers, Jacob probably making the 1864 rectangular Southern cross flags for the Army of Tennessee in early 1864. Charles also made the state presentation flag for Cobb's Legion which was captured at South Mountain.
I have files and invoices for both men and have never found anything for Mrs. Platt making any flags.