I’m pretty sure he was just asking the painter for a confirmation of something he already suspected because in chapter 85, which is where we first saw carcel get some of his memories, his inner monologue was asking Ines something along the lines of: “then did you already remember everything from the beginning?”.
This implies he already suspected she knew but never asked her which is why he’s now asking the painter for confirmation. Im guessing he didn’t want to ask Ines cause he wanted to wait for her to reveal it to him herself whenever she felt like she can since he said something similar to raul too.
There was a chapter where carcel was questioning raul and Raul did not want to answer and Carcel respected that, saying he did not want to force him to speak and would wait until Ines felt like telling carcel himself. I believe he is following through with that here by not brining it up to her first.
No, yeah, for sure! That's not what I'm confused about. I meant Emiliano. He said with such an unwavering certainty that she isn't like them. As if she doesn't know anything and can't do anything to change things, when she in fact did. And the first clue he should've caught up to is the fact that she did not hire him for the painting like last time, nor did she marry Oscar.

He of all people should know that Ines isn't just reliving things the same and letting herself get dragged by fate. Because in this time, she isn't with Oscar. She chose Carcel. As a kid, mind you, and that was all over people's mouths for a very long time, so he knows. What's he on about? Is that a plot hole or is he just dumb?