Renders from ACEScg working space to Rec 709 are not accurate

I'm working in ACEScg in Autodesk Maya. To test After Effect's OCIO functionality I exported a rec709 render directly from my 3D program and compared it to After Effects converting the orginal ACEScg file to Rec709, and noticed a discrepancy. I even noticed the viewer in After Effects seems to be slightly off, which makes me think After Effects just isn't accurately converting anything from ACEScg to Rec709? The Ae render is slightly darker. I tested again using Nuke doing the same thing I did in Ae and it matched the 3D render. After effects, what are you doing??