In this video Avery demonstrates his thermal camera project that he is working on:
The code does technically work. I put my hand over the sensor, and LEDs light up. In the video, they appear to get brighter because the led on/off decision is made by basically taking the image and converting it to on/off based on a threshold. The threshold is very close to the ambient temperature of the room, so it flickers on and off. Putting my hand over it makes it more likely to be on, so the display gets brighter.
However, there is some work to be done. The first thing to do is add ambient temperature compensation. The grid-eye has an internal temperature register that can provide a baseline value for what pixels are actually at ambient temperature. This could be sampled on boot or reset. Ideally, the brightness of each pixel would be proportional to the temperature (to some extent), instead of just thresholded.