Three codes could be found in the NIA Shard Manifestation Document post on the Investigate Ingress blog.
[1] 3o6x3rrcxteqv8p5
[2] 1600140412181010101412161406160014181412121810121006100014021410
[3] nek87ses239tu
Code #1
Observations
16 characters with the right amount of numbers for a valid passcode
Code #2
Observations
It’s all math from here
Code #3
Observations
Weird Niantic stuff !!!