Perhaps the modern/mainstream popularization.

Huh? Where do you think it originates then?

It's from Terry.

But the shortened, less overtly racist term 'Glowie' comes from 4chan and similar environs

"Glowing" was used as a description of government agents before Terry's "popularity"; the most common modern version is tongue-in-cheek "jokes" using the term while "outing" someone, usually someone who is asking odd, or personal questions, especially in a security or privacy community.

Do you have any reference to support your claim that "glowing" was used in this context before Terry's livestream?

You're hoping I'll permalink you to...decades old IRC and other chat and forum conversations?

Kind of? he never actually used the word glowie AFAIK. 4chan is the origin.

He coined the phrase which the word is descended from, infamously, on a video livestream

THAT part is true.

AFAIK that originated with the video where he said this:

NSFW: https://www.youtube.com/watch?v=AbG6u86t4bA

Then the word “glowie” was coined in 4chan based on that, as others commented here already.