JwtIssuerReactiveAuthenticationManagerResolver does not work while jwk-set-uri does

Question

So I need to support multi-tenancy and have read about it here.

I have followed the steps and added: the authentication manager (fake uri):

    JwtIssuerReactiveAuthenticationManagerResolver authenticationManagerResolver = new JwtIssuerReactiveAuthenticationManagerResolver
        ("https://jwt.com/token.json");

with the new oauth2ResourceServer:

        .oauth2ResourceServer(oauth2 -> oauth2.
            authenticationManagerResolver(authenticationManagerResolver));

but the code always returns 401. When using the same uri in the single tenancy, it worked successfully, so I am not sure what I am missing. Here is the old way.

yaml:

    oauth2:
      resourceserver:
        jwt:
          jwk-set-uri: https://jwt.com/token.json

with the implementation:

        .oauth2ResourceServer(oauth2 -> oauth2.
            jwt(Customizer.withDefaults()));

This successfully authenticates.

I do see a difference in the logs as well.

With the authenticationResolver:

2023-03-21 11:46:11.085 DEBUG 15271 --- [ctor-http-nio-3] o.s.w.s.adapter.HttpWebHandlerAdapter    : [cabda122-1] HTTP GET "/api/v1/redacted"
2023-03-21 11:46:11.136 DEBUG 15271 --- [ctor-http-nio-3] o.s.w.s.adapter.HttpWebHandlerAdapter    : [cabda122-1] Completed 401 UNAUTHORIZED

and the old way clearly calls the resource server and decodes:

2023-03-21 11:41:53.843 DEBUG 12500 --- [ctor-http-nio-3] o.s.w.s.adapter.HttpWebHandlerAdapter    : [963bfd7a-1] HTTP GET "/api/v1/redacted"
2023-03-21 11:41:53.932 DEBUG 12500 --- [ctor-http-nio-3] o.s.w.r.f.client.ExchangeFunctions       : [4740b9ba] HTTP GET https://jwt.com/token.json
2023-03-21 11:41:54.695 DEBUG 12500 --- [ctor-http-nio-3] o.s.w.r.f.client.ExchangeFunctions       : [4740b9ba] [3475d267-1, L:/10.26.8.242:58490 - R:jwt.com/99.64.754.467:443] Response 200 OK
2023-03-21 11:41:54.713 DEBUG 12500 --- [ctor-http-nio-3] o.s.core.codec.StringDecoder             : [4740b9ba] [3475d267-1, L:/10.26.8.242:58490 - R:jwt.com/99.64.754.467:443] Decoded "REDACTED"
2023-03-21 11:41:54.736 DEBUG 12500 --- [     parallel-1] o.s.w.s.s.DefaultWebSessionManager       : Created new WebSession.
2023-03-21 11:41:55.090 DEBUG 12500 --- [ctor-http-nio-3] o.s.w.s.adapter.HttpWebHandlerAdapter    : [963bfd7a-1] Completed 200 OK

So what am I missing to have the multi-tenant way actually use the resource server? I don't see any mentions in the docs.