Mythic Mobs command feature

In mythic mobs for the Skills, I'll add a command like this, but it doesn't work. It is bugged..

rogue1:
Cooldown: 4
Conditions:
- targetwithin 15
- TargetInLineOfSight true
Skills:
- cmd 'castp $world,$boss_x,$boss_z,$mobuuid flamethrower' >0 1