The greater rift guardian Vesalius does not display a ping on our minimap.
This is a problem when he spawns far away leaving the player(s) on a wild goose chase.
This problem has been happening for years and would hopefully be an easy fix in an upcoming patch.
Bug still presents. Not only minimap full-size map also doesn’t show it. Think it’s need to be re-reported after the PTR start.
unfortunately this has ben reported many times, yet the devs have not addressed it.
This may never get resolved 
I would say that’s the likely scenario given it has not been fixed in 6 years and the game is on the verge of being officially mothballed.
Just got this bug in the current PTR. Not only he doesn’t have a map indicator, he does not teleport to the player, no matter how far you walk away from him.
There are a handful of rift guardians that need to be agrod and will not teleport. This has been in the game since GRs were introduced.
Which ones?
20 characters
Cant remember but I have it written down on a spreadsheet somewhere. I think ghom and skele king?