So, you understand the functionality of pin 25. To restate, here is the relevant section from the TRBO CPS help
Options
Disable Ignition Off The radio powers on by following the ignition sense or power button. The radio will power off only by power button.
Follow Ignition Only The radio powers on or off by following the ignition sense on/off. The radio’s power button will be ignored.
On/Off Or Ignition The radio powers on or off by following either the power On/Off button or ignition sense.
TX Inhibit Activates the TX Inhibit feature when the radio senses that the ignition is off. The TX Inhibit feature prevents the radio from transmitting.
The only scenario that matches the behavior you are seeing is if there is a physical problem with pin 25, or the power getting to it. I have compared your images to an XPR accessory plug, and you are on the correct pin. Either you are not getting power to pin 25, or something is shorted or broken internally that is preventing the radio from reacting to pin 25.
What should happen is that as soon as you make pin 25 hot, the radio should turn on, and stay turned on until you remove power from pin 25.
I believe you have a damaged radio on your hands.