[He frowns a little. That's not exactly what he was apologizing for, but since he hadn't been at all specific, it's no surprise that Kokichi would realize what he was actually sorry about. How to put this...]

It's...more that I'm sorry that you had to carry that knowledge alone this whole time. Before the trial...Momota-kun said that he thought you were right...that maybe we should have watched the videos after all...and that we should have watched them together. And...I agreed with him at the time, and I still do now. But...after what we saw in Tojo-san's...we just went right back to thinking it would be better to leave them unknown.

[And with good reason, given what Kirumi said about hers acting as a flashback light. But...Kaito's clearly hadn't had that attribute. Otherwise he would have been affected by it, right?]

I should have...considered the fact that maybe Tojo-san wasn't the only one who got hers...that maybe there was someone else who didn't have the option to ignore them...

[He gestures vaguely, almost in a helpless sort of way.]

I'm just...I'm sorry that you had to go through that. I know it wasn't my fault and there's nothing I can do about it now but...I'm still sorry.

[Because somebody should be, he thinks.]