Other - Growing Amanitas

[The Dreamer]

My cat is interested finding a fresh supply of both muscarias and pantherinas. Since they do not seem to grow (at least not commonly) in his area he is wondering if he might find a way to cultivate them.

However, since both species are linked to certain types of trees they cannot be cultivated in a normal setting. What I'm wondering is: would there be a way around this? Like if he cut a section from the root of a tree or got a small tree in a large pot.

Does anyone have a firm idea of how these mushrooms actually interact with the tree and how my cat might replicate this indoors?