Sadly your pictures do show a model number that has the protection so it is not just a simple fault preventing the camera operation
The ‘activator’ was likely created by someone who had access to one of these cameras that was still in the host car. Monitoring of communications between the cars electronics and the camera likely revived the information needed to understand the protection system. You are in a difficult position as you only have the camera and no host electronics. Reverse engineering the cameras firmware might be an option but would be a lot of work.
Sadly you have to ask yourself whether the amount of work needed to get this camera working is worth doing. If you can buy the activator from someone on line that might be the way to go, depending upon the cost. You might have to do some deep dives on Russian sites to find a source though.
At the end of the day, these BST thermal cameras are now old technology with an unknown remaining life and they are bulky. More modern camera cores like the FLIR TAU2 with high frame rates are very expensive but a joy to deploy and use. Some cores like the FLIR VUE are designed for Drone use have only a video output and are sold at a reduced price.
In your position I would likely mark this one up to experience and begin hunting for an ex fire brigade thermal camera. These are normally decent resolution and high frame rate. You can then remove the imaging core and mount it in a custom weather proof case. Some fire fighting cameras use the BST cores but later models often contain the Raytheon Thermal eye A-Si or BAE VOx microbolometer cores.
If you want to stick with the BST core technology, you could look for a Cadillac De-Ville core and either restore it using parts from your Honda camera or find one that is in good shape. These remain an affordable 320 x 240 pixel high frame rate camera solution. These seem to pop up on eBay quite often. I have a couple that I will likely rehome but I have yet to finish restoring them.
Fraser