Cannot login to subwiki domain directly

I have a wiki instance bound via OpenID to jumpcloud. For testing purposes, I have two names applied:

• wiki-dev.XXXX.com
• kb-dev.XXXX.com

It contains multiple sub wikis like "itwiki" and "dummy". When both names are pointing to the main wiki, eg, top-level (not assigned as an alias to a sub wiki) it works as expected. E.g., I can log in with OpenID to both hostnames. The cookie domain is set to "XXXX.com" in context.xml. 

Now I set as an example "kb-dev.XXXX.com" as an alias to one of the sub wikis:

• Calling wiki-dev.XXXX.com works as expected
• When I now go to kb-dev.XXXX.com it shows only the subwiki as expected.
• But when I try to login directly to kb-dev.XXXX.com I get an error:
  I think it is because the URL 
  kb-dev.XXXX.com/oidc/authenticator/callback?code=XXXXXX&scope=openid+profile+email+address&state=XXXX
  does not exist when the name is bound to a sub wiki as alias.
• After I tried just to replace the hostname with wiki-dev.XXXX.com - of course not accepted because one of the codes did not match.

The above screenshot shows the error message. Meanwhile, I have no idea anymore how to fix this. This is a real problem because for various reasons.

Tnx