If it is totally false and now that the warranty is somewhat invalid, why not open the device apart and see if there were any damaged components?
Have you also tried other Nokia care stores? sure they could be far away but they maybe worth a try if your device wasn't damaged at all.
I really don't understand what is the whole kaboodle with Nokia SAT, never heard of them and it seems like either you tried to ask help from them or you didn't and think they are laughing at you.
Also I'm guessing at this point it might also be a good idea to check dmesg to see if the kernel reports the eMMC not as 32GB but as something else.
Is this device a second hand?Dropped the device onto a hard surface. Dropped the device into water. Left the device in an area of high humidity. Overclocked the device.