after looking at your 2nd video, I would check the alignment of the bulb inside of the light tunnel. when you panned towards it, it looked like the light was being directed towards the front right corner of the cabinet and not directly straight forward.

the angle might be off just enough that the mirror isn't picking up the light to direct it onto the hologram. additionally, your hologram looks on its way out since your creature shows up a dark blue (when hit with the full intensity of your flashlight).

I'll try and throw my machine back together this evening to the point where I can shoot a video of the hologram test mode and you can see how my bulb, light tunnel and mirror are arranged.

lastly, I would take a clean microfiber cloth and attempt to clean your mirror (be careful. it's made of plastic, not glass). like most routed machines, it looks like years of dust and grime have accumulated on it, which can also affect the light being directed towards the hologram.