They claim to be making fake retinas, not that they actually work. I would imagine the device is fully capable of measuring anterior chamber depth and the like making any image/display just not work. I should query my optometrist brother-in-law about that sort of thing.
Part of my does wonder if other mammal eyes work though, I could see someone reaching out to their friend that volunteers at an animal shelter and being like "yo, let me in after hours and let's scan doggo eyes and make a little extra money".
It's a hoax.