Edit in Office opens MS Word document with empty content on Data Center (clustered) enviroment

Step to reproduce:

1. Set up a 2 node CDC cluster (change Hazelcast port on second node if setting both nodes on same machine)
2. Configure a load balancer in front. I used Apache HTTP Server with mod_proxy_balancer module. My configuration (I had "mydomain.com" set to point to my own machine via the hosts file):

   <VirtualHost *:80>
   ProxyRequests off
    
   ServerName mydomain.com
    
   <Proxy balancer://mycluster>
   BalancerMember http://127.0.0.1:8888 route=node1
   BalancerMember http://127.0.0.1:9999 route=node2
    
   Order Deny,Allow
   Deny from none
   Allow from all
    
   ProxySet lbmethod=byrequests
   ProxySet stickysession=JSESSIONID
   
   </Proxy>
   
   ProxyPass / balancer://mycluster/
   ProxyPreserveHost on
   </VirtualHost>
   

3. Edit setenv.sh and add -DjvmRoute=node1 and -DjvmRoute=node2 to start up parameters on each node, respectively
4. Edit server.xml and add proxyPort, proxyName, and scheme so that they point to the front-end (in my case, http://mydomain.com:80).
5. In Confluence Admin > Office Connector, enable checkbox to allow ocauth tokens to be passed in the URL
6. Upload a Word document
7. Attempt to use Edit in Office

Expected behavior

Word opens the document and displays the document contents as expected. Changes are saved back to Confluence via WebDAV

Actual behavior

Word launches, but no document content is loaded as Word is unable to download the document from Confluence WebDAV
May need to try several times to get this to fail, as the problem only occurs when the Attachment page is accessed via one node, but yet the Edit in Office tries to open the document via another node

Root cause

In the failed case, WebDAV can not get authentication to open the Word document