From what I remember, he would be fine with being tried in a Swedish court. He just wanted a guarantee of no US extradition, that Sweden would not provide.

Quite the opposite. He has been asking Sweden to guarantee that he will not be extradited to the US, and in return he will face trial in Sweden. They are still trying to negotiate this.

He has criticisms about what has happened in Sweden, no doubt. But it's the prospect of going near a US prison that is the non-starter, and the basis of his asylum.