I kinda get you're missing the point of what I said. First of all, the orphans I used as examples are mentioned in his supports. His C and A support to be exact.
After re-reading these however, it turns out he merely captured the children. Which does mean he must have killed at least one child off-screen, but we have no way of knowing whether they were "innocent" or hostile. Considering the context however - the full blown war with children losing loved ones left and right - it is more likely he was attacked by children.
At least only one child, you may ask? Yes, as not having directly killed Fleche himself does not mean Dimitri can not feel responsible for her death. As the support proves, he could have easily disarmed Fleche, stopped her in some way, and prevented Rodrigue and Fleche from dying.
Oh, and thinking about it... didn't Edelgard try to assassinate her fellow students multiple times? Before the war? You know, when they were under 18? "Children", one might say.
Which kinda brings me back to this. Edelgard was aware of who Dimitri was: her childhood friend/step-sibling. And I don't remember Dimitri allying with Rhea before the war, huh, weird. And you are telling me she only invaded Faerghus because he allied with Rhea? Why try to assassinate him then?
But heavens, this thread is hardly about Randolph and Fleche anymore and is devolving into a Dimitri bad/Edelgard bad thread once more. I think imma stop bothering with this, maybe we can pick this up in a more appropriate thread, hm.