The first thing to note is that Buddhism is a broad term that contains a lot of different belief systems. It is also plagued by poor translations of terms that don’t translate well into English, especially without looking meanings of the original terms.
Imo, your friend has distorted and misrepresented Buddhist teachings in order to justify not changing their behavior regarding meat-eating.
I’d challenge the use of the term “deserved” altogether, and I’d say “caused” might be a more accurate interpretation. Karma is not about an intelligent, all-powerful being passing judgement and smacking you down. It’s sometimes referred to as “the law of cause and effect.” It’s described as a function of the universe, the same way that physical laws makes objects fall to the ground when dropped. The exact way in which this works is up to interpretation. More secular-minded Buddhists might point to logical and observable consequences to explain it, while more spiritually-minded ones might argue that it’s more of an invisible, unexplainable force that carries over between lifetimes.
To use an example: a child that is fed a hamburger by their parents does not have knowledge of the animal’s suffering that was required to make it, nor do they have agency to control their diet or to prevent the animal from being harmed. But, an animal is still harmed through the process. The intent and agency of the actor are not important in the same way that it doesn’t matter if a ball on top of a slope is pushed or knocked over. It would only really matter if you’re dealing in terms of judgement.
It is not your responsibility to enforce karma on others. Karma isn’t a positive or negative force, and just because something happens that doesn’t make it good or fair or deserved. Rather, the idea is to navigate the world in such a way that you minimize undesirable consequences. Buddhist precepts are a list of guidelines that are intend to do just that, the precept about nonviolence being the first. The idea is: “Bad things seem to happen a lot when people go around killing living beings so it’s probably better to not do that, generally speaking.”
You are correct that your friend’s interpretation and worldview is a mess of contradictions that could just as easily be used to justify harm to humans, and that they’re blatantly violating the first precept. But I would argue that they’re not accurately representing Buddhist teachings, and their views shouldn’t be held as representative of the belief system, though admittedly, like I said there are a lot of different traditions and beliefs.
Frog speedrun any%