It's easy,

…if you don't speak Korean, feel free to turn to your cheerful friend

Google

The translation from Korean was a bit misleading. 🤔

Instead of "Glowing place", it's better to use "Lighted place"

(the place is not glow, but is illuminated)

Forget GM, the best indication is " light "

from an external source!

My advice, take a screenshot of a place that is illuminated by external light

-> your chosen place, which probably applies to the description.

If you have the right place, then "Go" will be replaced by "Claim reward" in the Event tab

and you will be able to collect your reward.

Good Luck 
JAACO