2018 Forester, std. key, where can I find Neg. output for Rear Defrost (location and wire color)

Question

Trying to use yellow/black Aux1 connection, for Rear Defrost. (Wirecolor.com has it as, Purple/Green Behind dash fuse box, plug (A) Pin 26) I'm assuming this means BCM Behind fuse box. "Plug A" is plug #1, on Fortin's installation instructions. There in no Purple/Green wire at that location or anywhere on that plug. Any help would be greatly appreciated.