Need frame's to Hide during Cinematic

[Mayron]

Hi, I have an issue with an in-game cinematic where frames show over it. Usually I would use:

local frameEvent = CreateFrame('Frame')
frameEvent:RegisterEvent("CINEMATIC_START")
frameEvent:SetScript('OnEvent', myEventHandler)
function eventHandlers.CINEMATIC_START()
    playerGradient:Hide()
    targetGradient:Hide()
end

however I don't think the "Deathwing's destruction at the Maelstrom" cinematic actually counts as a cinematic which is the problem. When I go in Orgrimmar as a Horde and right click on the NPC and select "Show me, dragon." to play the cinematic I get this:



Does anyone know the reason why or how to fix this? Thank you!