If the official firmware loader won't load the official firmware this is out of our control.
The way the firmware loading works, is that the radio has loader firmware installed by TYT at the factory, which is activated when you apply power to the radio while holding down P1 and Orange. This loader firmware is called the "bootloader".
The bootloader allows the main application firmware e.g. openMD9600 or the official firmware to be installed into the radio CPU either using the official loader or the OpenMD9600 loader
The OpenMD9600 loader exe can only load OpenMD9600 firmware and the official loader exe can only load the official firmware files.
Personally I found the official loader to be unreliable and would fail to upload or crash about 10% of the time.
But it sounds like the official loader is even worse for you.