Katello 4.0.1-1 / Unable to sync Debian 10.10 Buster .deb content to Smart Proxy

Problem:

I am able to sync Debian 10.10 content from Index of /debian/ however after creating a content view / LCE and adding the LCE to a smart proxy all future syncs fail.

If the Debian related LCE is removed from the Smart Proxy I am able to sync CentOS 7/8 Content fine (with the synchronizing.py lzma related code fix in place)

Expected outcome:

The Smart Proxy is synchronized with the deb content.

Foreman and Proxy versions:
katello-common-4.0.1-1.el7.noarch
foreman-2.4.1-1.el7.noarch

foreman-proxy-2.4.1-1.el7.noarch
foreman-proxy-content-4.0.1-1.el7.noarch

Foreman and Proxy plugin versions:
N/A

Distribution and version:

CentOS Linux release 7.9.2009 (Core)

Other relevant data:

Error message: the server returns an error
HTTP status code: 400
Response headers: {"date"=>"Sun, 04 Jul 2021 10:40:39 GMT", "server"=>"gunicorn/20.0.4", "content-type"=>"application/json", "vary"=>"Accept,Cookie", "allow"=>"GET, POST, HEAD, OPTIONS", "x-frame-options"=>"SAMEORIGIN", "content-length"=>"45", "correlation-id"=>"9b294d8384724e2b85c8ed41cbb21fad", "access-control-expose-headers"=>"Correlation-ID", "via"=>"1.1 lab0l06.virtual.home.arpa", "connection"=>"close"}
Response body: {"distributions":["This field is required."]}Error message: the server returns an error
HTTP status code: 400
Response headers: {"date"=>"Sun, 04 Jul 2021 10:40:39 GMT", "server"=>"gunicorn/20.0.4", "content-type"=>"application/json", "vary"=>"Accept,Cookie", "allow"=>"POST, OPTIONS", "x-frame-options"=>"SAMEORIGIN", "content-length"=>"82", "correlation-id"=>"cbd26ab08e0b4fe3b3707f390c187a0a", "access-control-expose-headers"=>"Correlation-ID", "via"=>"1.1 lab0l06.virtual.home.arpa", "connection"=>"close"}
Response body: {"remote":["This field is required since a remote is not set on the repository."]}Error message: the server returns an error
HTTP status code: 400
Response headers: {"date"=>"Sun, 04 Jul 2021 10:40:39 GMT", "server"=>"gunicorn/20.0.4", "content-type"=>"application/json", "vary"=>"Accept,Cookie", "allow"=>"GET, POST, HEAD, OPTIONS", "x-frame-options"=>"SAMEORIGIN", "content-length"=>"85", "correlation-id"=>"af68842c17034224adff2866c21955d1", "access-control-expose-headers"=>"Correlation-ID", "via"=>"1.1 lab0l06.virtual.home.arpa", "connection"=>"close"}
Response body: {"non_field_errors":["one of simple or structured publishing mode must be selected"]}

This is a fresh install of the OS and Katello software, SELinux is permissive, plenty of disk space (600Gb) and required memory (20Gb).