yum install fails on GPG check of repomd.xml if content has been modified

When the yum client is configured to require GPG check and the contents of the repomd.xml have been rewritten the GPG check will fail with the following error:

http://localhost:8081/repository/newrelic/linux/yum/el/7/x86_64/repodata/repomd.xml: [Errno -1] repomd.xml signature could not be verified for newrelic-infra

This is reproducible using the remote:
https://download.newrelic.com/infrastructure_agent/

The repomd.xml on the remote contains sqlite entries which are removed when the repomd.xml is written to the proxy repository. So the two files do not match.