Investigate better error message when OIDC discovery fails

ASP.NET (4.x especially) tends to throw really unhelpful errors when retrieving the discovery document fails. For example: https://devforum.okta.com/t/401-status-on-login/3615

Is it possible to hook into any part of the MS OIDC middleware to detect this, and at the very least, throw a more helpful error message?