I personally call them out in chat politely.

“Hm, I wonder why ‘X’ is still over by the first mobs? AFK maybe?” Then I will stop, typically right before Lahabrea, make sure everyone knows it’s about to happen, initiate votekick, and theyre kicked. This gives them plenty of time to get their butt into gear and join up. It also means that if they’re AFK for rewards, then they’ve just wasted 45 minutes of their life and now have to queue again AND go thru another 45 minutes again.