Just got a new error (at least new to me) at around 6:40PM EST.
That message now appears because the host suggested I update the site files even though 2 domains running different versions are having the same problem. I can update the database but I don't think that is the cause of the problem, as it seems that it sporadically loses some of the connection to the database.
They are now telling me that it is because of what I have set as the database username on another domain - which would be funny if it wasn't so important.
I am getting nowhere with the host so I am going to request migration to a different server or just cancel this account for a U.K based account which is more expensive but far more solid.
Hopefully this update will post when I press the button, but if not I'll mail it out.