True or not, here are my assumptions:
Amiibos are 540 bytes. Even without knowing how to encrypt/decrypt them you can have 4320 possible combinations (which most of them wont be valid anyway). A subset of those 540 bytes is for the meta-data and the others are stuff like level, abilities etc (it really depends on how each game uses that space)
Now unless big N makes amiibos that store more than 540 bytes, you can generate 4320 different amiibos (which most of them will be invalid but you need zero knowledge and no crypto-analysis).
So if lets say 100 people have bought the amiiqo hardware and are willing to contribute, all they have to do is take a batch of 44 "roms" (I know its not the proper term) and mark which of them actually work.
The problem is when having a legit amiibo that works on game A but its being tested on game B instead so it is found as an invalid one.
