As said above, dont spam soulshards, affli is all about uptime of dots on all targets and shards management.
That being said, the general rule is you wanna stay at 2-3 shards most of the fight.
Have ...
WoW Freakz link: https://www.wow-freakz.com/quest_helper.php?quest=45969&name=defense-of-the-ancient
Bug description: There are no mobs around, not phasing or something like that... Its a rare WQ ...