Incorrect OpenID Config URL

[coolaj86]

Your sandbox developer API is NOT OpenID compatible.

No OpenID client can get the details for the sandbox because the URL is arbitrary rather than based on the environment's domain name.

Bad URL

https://developer.intuit.com/.well-known/openid-sandbox-configuration is INVALID.

The discovery file MUST be named EXACTLY /.well-known/openid-configuration from the base url.

Possible Fix

It should be something like https://sandbox-developer.intuit.com/.well-known/openid-configuration

(or https://sandbox-quickbooks.api.intuit.com/.well-known/openid-configuration or maybe even https://developer.intuit.com/sandbox/.well-known/openid-configuration, etc)