Not a spoiler just super speculative, but was he not brainwashed or something? I’m convinced he worked with the magician to do the time travel spell, which might mean that he has fragmented memories of what happened before without truly understanding the purpose. I mean, the reason why he looked so shook when the girl repeated herself is that this is the first time an event happened in sequence like that. Like a really bad case of deja vu. MC has been doing a lot of things differently up till now so he may have thought things were odd but nothing as specific as this.
Also, I think they are both his daughters. Rather than worrying about who gets magical powers or not he should really try to investigate if she’s after his big money. Lol
Another reason why I think he had some brainwashing spell over him because he did not seem to be the least bit concerned about her scamming him either financially nor supernaturally, even though he had every reason to be cautious. Family from dead ex-wife shows up and...nothing? Weird.