'all' arch apparently not honored by repo

Packages of all architecture added do not seem to be part of the manifest.

steps to reproduce:

• add a package that is not (say) amd64, but 'all' in architecture. note that binary-all does get created and updated.
• add the repo to apt (see below)
• run apt-get upgrade
• run apt-get install packagename, where packagename is not an amd64 package, but rather an all architecture package.

expected result:
package gets downloaded from nexus and installed

observed result:
E: unable to locate package sample-package

example of object from repo:
package_name: sample-package
package_version: 8.0
index_section
Package: (description snipped)
asset_kind: DEB
architecture: all

nexus.list:
deb http://user:password@nexus.example.com/repository/my_repository trusty main

P.S. Copied from https://github.com/sonatype-nexus-community/nexus-repository-apt/issues/105