Besides the obvious bugged spawn on the Hallowfall one, this system needs to be changed.
A spawn on a 6h cooldown, that can randomly spawn on any of the 4 zones which despawns a few seconds after being used, having a very long cast time to open that can be interrupted by random aoe makes no sense, even in a world pvp setting.
Right now the only way to open the chest is to have enough luck to be in the zone it spawns in and have noone from the opposing faction around.
Make it more frequent, on a set rotation between the zones, increase the timer it stays up since being first looted and set a lockout on the socket item so it can’t be mindlessly farmed.