KSP 1.9.1, ckan 1.27.2
Im not sure if its a problem with KAS or with ckan?

The problem is in CCK dependency which is marked incompatible with 1.9.1. In fact it's is compatible, but CKAN doesn't know it, so it hides all mods that depends on CCK. KIS and KAS included.

As a workaround, mark version 1.8 as compatible.

It should be visible now.