Firstly, I would like to say that what happens in the animal world has no bearing on morality. You said it yourself, morality is a human thing. So a lion is not a moral agent, I would not judge it for eating a zebra, nor do I believe that we should try to prevent it from doing so. However, just because animals do something, it does not mean it is not immoral for us to do so, it is as natural for certain animals to eat humans, as it is to eat other animals. That does not mean that murder is moral now, suddenly. Similarly, it is not the case that because it is not immoral for animals to kill other animals(they are not moral agents), it is ok for us to do so.
Secondly, the words direct/indirect do not mean intentional/unintentional. I do not think it is sensible to claim that the more removed you are from the consequences of your actions, the less moral responsibility you bear, but it seems to me like you are excusing the behavour of carnists(that word is, as another commenter put it, metal as fuck) by claiming that most of them are ignorant of the consequences of their actions, but this has nothing to do with how “direct” the act is. I would like to add that the reason for the ignorance of most meaters(meat eaters) with regards to how the animals are treated is their characters, they are keeping themselves in ignorance and are resistant to attemps to enlighten them.