I thought uat said that the picture wasn't alerted and is shown as is...so why did uat photoshop the (As) on the gowns?
They didn't. Edges typically have higher ELA values due to the stark contrast in colors, and thus will show up as brighter. It's not a perfect method of detecting photoshops, but it's pretty accurate. It's basically comparing the compression levels throughout the image, and more often than not, the compression level for a photoshopped section of an image will be high enough that it will show up as white with this ELA method. Resaving the altered image can affect this, but the altered area would still be noticeably brighter than the rest.
Also, if the image was saved with Photoshop, the program will often automatically sharpen edges, which can result in edges showing up as lighter in the ELA simply due to a save.