Killed Zek\'voz twice in same heroic uldir run

Did a random Uldir HC run with my guild this Friday, somehow we managed to get loot from Zek\'voz twice. NO idea how to reproduce this because it just happend by chance.\r\n\r\nDid the fight as per normal, at 0,2% the boss despawned out of nowhere, we ALL received \'loot\' from the boss (sanguicells, actual gear, gold etc) which got sent to our mailboxes.\r\nThere was no corpse present as he did actually despawn and our raidlockout did not have Zek\'voz checked. Proceeded to actually kill him the 2nd pull and we all got loot again (now directly from the corpse rather than our mailboxes).\r\n\r\nAs stated above I have no idea how this happend and I got no \'proof\' of it happening. Figured I\'d post it if someone got an idea of how to reproduce it - however this feels very bannable.