Hmm, new code is doing the following which should read the friendly name not the edid name.
Code:
// We skip edid.identifier because it is unreliable, and a better option
// is already available through DisplayConfigGetDeviceInfo (see below).
names << QString::fromWCharArray(deviceName.monitorFriendlyDeviceName);
so I have no idea unless it is reading a different friendly name than the one you set.
Strange!
Have you tried a full restart to force-all new values to be read?