In order to enable Altmetric Explorer for Institutions access via your EZProxy server, Altmetric requires the following database definition in config.txt:
Title Explorer for Institutions
HTTPHeader Origin
HTTPHeader -request -rewrite Origin
HTTPHeader X-CSRF-Token
URL https://altmetricexplorer.com
Host https://www.altmetric.com
Please note that the starting point URL should be something like: http://ezproxy.myinstitution.edu/login?url=https://altmetricexplorer.com
That's it! Your users will then be able to access Altmetric Explorer for Institutions off-campus via your proxy server.