When using HTTPS Index.html showing instead of ProxyPass reverse proxied site on Centos 7 Apache 2

The goal is that external users can connect via HTTPS, go through basic auth on Apache and then view a proxies tomcat site.

I have set up a reverse proxy to a tomcat server running on the same machine on a different port with basic auth: (/etc/httpd/conf.d/vhost.conf)

NameVirtualHost *:80
<VirtualHost *:80>
    ServerName  sub.domainx.co.uk
    ErrorLog "/var/log/proxy/domainx_prox_error_log"
    CustomLog "/var/log/proxy/domainx_prox_access_log" common
    ProxyRequests Off
    <Proxy *>
        Order deny,allow
        Deny from all
        Allow from all
    </Proxy>
    <Location />
        AuthType Basic
        AuthName "Proxy Auth"
        AuthUserFile /var/www/syzygy-auth/CONFLUENCE/.htpasswd
        Require user ukuser
        Satisfy any
        Deny from all
        Allow from 192.168.0.0/21
   </Location>
   ProxyPass / http://sub.domainx.co.uk:8090/
   ProxyPassReverse / http://sub.domainx.co.uk:8090/
</VirtualHost>

The above works fine.

I then went about setting up mod_ssl on apache.

yum -y install mod_ssl

I then uploaded my wildcard ssl and made the dollowing changes to /etc/httpd/conf.d/ssl.conf

uncommented: 
DocumentRoot "/var/www/html"
uncommented/updated:
ServerName www.server.world:443
SSLCertificateFile /etc/pki/tls/certs/server.crt
SSLCertificateKeyFile /etc/pki/tls/certs/server.key

These changes appear to have had the desired effect.

I can not view index.html via HTTPS and HTTP proxies the tomcat server.

When I add an identical vhost but with the port changed to 443 no changes take affect.

When I added SSLProxyEngine On apache would not start.

I got the following in the proxy error logs:

Fatal error initialising mod_ssl, exiting. See /var/log/proxy/domainx_prox_error_log for more information

Server should be SSL-aware but has no certificate configured