[Apt-cacher-ng-users] Trouble caching dell packages from community repo

[E V]

I have an apt-cacher-ng server running debian stretch, and it's
failing to update the Dell repo's at:

http://linux.dell.com/repo/community/debian/
and
http://linux.dell.com/repo/community/openmanage

Not sure why exactly, but it seems like there aren't .xz versions of
the Packages files so that might be related. The apt-cacher expiration
page lists:

Error summary:
linux.dell.com/repo/community/debian/dists/jessie/Release: 500
Connection failure: Connection refused

 Any ideas how to get this working again?

Removing the apt-cacher-ng from the equation and apt-get updates just fine.

Thanks,
-Eli