As of b3b6aae, the structure of the NIP-46 request (nostr.api.NIP46.Request) is not correct.

According to documentation, the request should be of the following structure:

{
    "id": <random_string>,
    "method": <method_name>,
    "params": [array_of_strings]
}

(Source: https://github.com/nostr-protocol/nips/blob/master/46.md#request-events-kind-24133)

I made related comments here: b3b6aae

In the meantime, I'll work on creating a simple test to produce the problem I expect from this code.