Click the orb to summon the trash while the raid is on Heroic mode, then switch it to Normal. Hagara will be standing at the back of the trash. Smack her and aggro the trash (she isnt linked to them), vanish/feign/wipe and the trash event will be gone with Hagara alone waiting in the middle like normal.
Was laughing pretty hard but did think to take one screen shot:
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