I was watching All In from this past summer, and kayfabe it'd make sense that she'd appear in the audience and then immediately after we see her in the crowd the devil stuff starts.

I think where they'd go with it is as Mercedes wanting to be the biggest thing in AEW immediately and having to remove MJF to make a statement. It makes sense the more I think about it as, who would be fine making MJF lose the belt as part of their plan to target him without wanting the belt for themselves? It'd be someone who wouldn't be interested or able to challenge for that title.

It's bigger than being champion.