[Caellian]

But i'm not interested in any specific loot, i just want to know if i looted it, not what was inside

So basically, you're saying something like this would suffice ? (untested, drycoded)

local champions = {"Deathtalon", 95053, "Doomroller", 95056, "Terrorfist", 95044, "Vengeance", 95054}

if event == "LOOT_OPENED" then
	for i = 1, GetNumLootItems() do
		local GUID = GetLootSourceInfo(i)

		for id = 1, #champions - 1, 2 do
			if string.find(GUID, champions[id + 1]) then
				C_Timer.After(5, function()
					C_LFGList.RemoveListing()
					LeaveParty()
				end)
			end
		end
	end

	self:UnregisterEvent("LOOT_OPENED")
end