Look, Henry's imagined a lot of people showing up in this place. Emma again, his grandparents maybe. So when he rounds a corner and immediately sees his mom, it's...fine, everything is fine.

Until he realizes how she's dressed.

"...Mom?" He's wary, looking at her in confusion. "Why are you dressed like that?"

Because it never crosses his mind that this would be any other version than the one who's been with him the entire time he's been in Wonderland.