Simply put, if you press Void Cleave while channeling Warpath, it is more likely than not that your character becomes completely unresponsive until you press Warpath again.
This was tested in The Lesser Refuge and The Ruined Temple.
I’ve been experiencing something similar, when i’m channelling warpath and try to do a void cleave or a Abyssal Echoes, most of the time the character use the skill animation but the skill itselt don’t cast. It’s really annoying. Lung has a similar problem, but instead of not casting it just do a mini lung that don’t get to the enemy, almost like warpath cancel the lung in the middle of the dash.