I do think, if Ridley happens to be a stage hazard, he'll be shown as such during a new trailer, rather than a mere update (like a higher-profile Yellow Devil). It would essentially be a half-arsed way of giving him a character-esque reveal, without him actually being a character. I'll echo SSBF in claiming this could backfire in terms of people being pissed by the anti-climatic nature this would have, but I see it as Sakurai's way of trying to appease the Ridley fans he knows he's letting down, kind of like making him two bosses instead of an Assist Trophy may have been.