Follow the white rabbit 3/4
The person who posted the video seems to be a friend of agent Smith, they met in a park. We count on you to find the name of this place.
(The flag is the name of the complete park copied/pasted)
Flag ECTF{Name_of_the_park}When we look at the youtube channel, in the about part we can find the mail adress of Kevin Larson.
Now we can use that email adress with GHunt 🕵️♂️ and found one google maps review associated : https://www.google.com/maps/contrib/115692578389258734621
ECTF{Královská obora Stromovka}or ECTF{Královská obora}