Open Access Start over Firewall Error

Squared Up is working within my domain and so is Open Access.
We provide the Open Access over to another domain, via Firewalls and NAT’d to another address.

Using version 4.7.1 and getting this result on the other domain - “Squared Up cannot start due to an error”

Looks similar to this site but we’re using v4…

Are there some steps someone can tell me to check to troubleshoot this further?
This is hard to troubleshoot using the suggested steps on the site, because it is working fine within my domain

The dashboard just came good by itself over night.
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