For the first I think not being trained and having the knowledge of surgery is categorically different, so I don’t think that critiques holds up.

Rule is don't do anything unless you want it to be universal. It doesn't say if the training levels are different.

For your last point i think the rationalzation would be: “Punishing people for bad behavior is something that if everyone did would be good.”

Right except this won't work. We can't have the entire population be judge, jury, and executor. Which means we have to designate certain segments of the population to be specialized in punishing people. Breaking the universal nature of the categorical imperative.

The whole thing can't be fixed. It lacks all context so what people try to do is add context in. And the reason why it lacks all context was Kant was working backwards. He wanted the thou shall and thou shall nots morality of the bible without God given revelation. The only way to pull this off was make man replace god, all powerful and all weak at the same time. Humans were to be their own judge of what was right and wrong with no one's opinion better than anyone else's. At the same time any rule they declared they were bound so strongly that it crippled them. Morality isn't a way for humans to live happy lives with each other, morality is to be a chain that we ourselves made and bound ourselves with.

Don't worry however, sure you had to watch your kid die of starvation rather than steal bread, Kant is firmly convinced God will even the score in heaven.