Verify subscription status in constrained environment

With Creative Cloud apps installed in a network-constrained environment, what exact URL do we need to allow to just verify the subscription status regularly? 

The client (Windows) PCs cannot access the internet. We can allow  access to specific designated sites but not all.  

We do not use any cloud services on those PCs, we don't store docs in the cloud.

I tried the "minimal" list of URL as given here https://helpx.adobe.com/enterprise/kb/network-endpoints.html,

but when we do that, the apps freeze after a few minutes.  In the Task-Manger,  a process called "Adobe Crash Processor" becomes active. There are no error messages of any kind. This happens with InDesign and Photoshop - which is the primary apps we use.

If it is important - the way we allow the URLs in the Adobe site list is by adding conditional forwarders for each of the sites in the Windows DNS server, and allow the FQDNs in the firewall. Verified with a couple of those sites that name resolution works and can reach sites such as adobe.com.

My suspicion is that the app like InDesign is doing some background processing using one of these whitelisted URLs but those processes demand the use of further URLs which are NOT in the list given by Adobe, so pieces of the processing fails, causing the entire thing to hang. Sounds like a very brittle application design if you ask me, and it might not be how it is - but as soon as I disconnect the machine from the network, restart it and work on local files, everything behaves normal again.

So is this "minimal" list not complete?

It seems way too large already - we don't need and don't want any cloud "services", don't want any automatic updates. If we decide to update, we can put the PCs on the internet for a day and do the updates manually. That's what works for us.

Just want to verify the subscription status automatically.

I would expect that there is one or two URLs we need to whitelist, and that's all.

So does anyone know those one or two URLs which would be needed just for subscription status verification?