Apache SAML authentication


I am using Mellon module on Apache webserver for authenticating with Okta. I am able to successfully authenticate user with Okta. The Apache webserver is acting as a proxy server for AWS elasticsearch/Kibana. After authentication, I would like to automatically redirect users to ElasticSearch/Kibana. Is it possible? I tried ProxyPass but I am getting a 404 error. It appears that Okta is sending a POSt request after authentication. Any help would be greatly appreciated.
<Location /_plugin/kibana>
ProxyPreserveHost On
ProxyPass /_plugin/kibana <kibana_url>
ProxyPassReverse /_plugin/kibana <kibana_url>
SSLProxyEngine on
SSLProxyCheckPeerCN off
SSLProxyCheckPeerExpire off
SSLProxyCheckPeerName off

This is what I am trying to achieve:
Webserver–> okta --> webserver --> EleasticSearch/kibana