[chronotrig]

It doesn't hint at anything you are describing. It's just unusual behavior from two characters who are supposed to be pieces. They are commenting as if they are fictional characters aware of the fictional framework in which they exist. Nothing about their conversations suggests they are acting out of character for what they are as characters, nor suggests they are one existence. That's absurd.

Personally, I'd say that a character acting in a way that's impossible is a fairly huge hint, much bigger than some slight differences in how they behave in separate episodes. I think it's hard to argue that they really encountered a person who performed magic on them, or even who they thought performed magic on them, and who was planning to kill everyone on the island to regain her full magical power. Sure, it's possible, but I think anyone can see that it's fishy. Also, you sort of brush aside the fact that they comment about other worlds. It might not prove anything, but I don't see how that is somehow less suspicious than a person's behavior changing.

You call Kinzo's behavior inconsistent, but can you provide some concrete examples of how? You demand examples from Shkanon supporters, so this is hardly an unfair request. It needs to be something more solid that "well, in one game, he decided not to write a will, but in another, he reluctantly agreed". That's not a change in character, it's just a different decision he made, and could have been caused by a slightly different series of events preceding the story or after the story starts.

The absence of evidence is not evidence of absence. The fact that Battler fails to see a corpse is not proof that there is no corpse. The fact that Battler does see a corpse is proof that a corpse exists. The consistent destruction of the corpse is evidence suggesting that the corpse, in its undamaged form, would be suspect for some reason. Based on this and the circumstantial evidence, it is trivial to conclude that Kinzo was dead prior to the 5th.

You're speaking in absolute terms here, as though there's something fundamentally different about the two cases, but I think the real difference is in how obvious the answer is.

I'll take EP4, since it's the easiest to argue. According to Battler, Kyrie claimed that Kanon's corpse fell into the well as they were climbing out. It seems very unlikely that it was even possible to enter or exit the well, so this part is almost certainly a lie, either by Kyrie or someone holding Kyrie hostage.

So, why would anyone lie about this? If we use your own reasoning, the most likely reason for hiding a corpse is because the corpse, in its undamaged form, would be suspect for some reason. Why would Kanon's corpse be suspect? Unlike Kinzo's case, the answer isn't obvious, but the problem is still just as clear.