Three codes were hidden in the HTML source of the LURE post on the Investigate Ingress blog.

[1] 9unknyyc5gtx5i5qof

[2] ugwtqrfhfrmvswvaq

[3] 7xls3xXvvGuhn2ypk4p1n

Code #1

Observations

18 characters with the right amount of numbers for a valid passcode

Spoiler

Make a 3×6 grid

Reverse rows 2, 4 & 6

Read going down from the upper left 9

9yyx5functionk5g5q

A roman emperor will get you the keyword. After just analyze closely what you have

Spoiler

Rot 13 reveals the keyword

htjgdesusezifjind

Let’s split into the format using 2 characters for each numbers

ht jgd es use z if j in d

The numbers are written in reverse

th jgd se use z fi j ni d

3jgd7usez5j9d

Modify thing to get a valid prefix and suffix, then Google is your friend

Spoiler

Atbash letters and numbers

3coh7cCeeTfsm8bkp6k9m

Split into the passcode format

3coh7 cCeeTfsm8bk p6k9m

Searching the middle string on Google gives a YouTube video by Mark Osborne called More

3coh7morep6k9m

The passcode return as invalid. Remember we used Atbash as the first step, the opposite of more is less

3coh7lessp6k9m