How to retrieve value of "Player Start Tag"?

Here’s the challenge:

I have some 20 PlayerStart actors spread out over my level, some are tagged with “Walker” and some with “Glider”. When re-spawning I want to choose a random “Glider” start (when I’m gliding).

What I’m trying so far:

  1. When in GameMode or PlayerController, I’m getting all PlayerStarts with “Get All Actors of Class”.
  2. Loop through the array and check with “Actor Has Tag” if the tag matches. If so, I put the PlayerStart in a separate array
  3. Pick a random entry from said array

The problem that I’m having is that there are zero matches. And what’s causing the problem is that I don’t manage to read the Tag of a PlayerStart. Even when directly trying to read the tag, it says “not in scope”.

What am I doing wrong here?

(see below an excerpt of the GM function)