I'm pretty sure the answer is 'no' but... does Mocking Banner taunt the motes/shards on Mythic Tectus (thinking about the aoe zerg phase)?
On our attempts so far I've dropped it but haven't noticed if it's taunting them or not - more focused on not dying I have to admit. I've tried the vigilance tab/taunt spam but that's time I could be using on making sure I survive if mocking banner is working.