Only other thing I can add that may help pin down the problem is this ... the homepage will work perfectly - but only if I am logged in as a user in the frontend first.
To do this, I have to take the website offline to prompt a login (because I do not have a login module published on the website). I go to any url for the website that is not the homepage - because the other pages will load. Once logged in, I can then navigate to the homepage and it loads perfectly.
Without logging in, I can load any page for the website that I know the url for - except the homepage. The homepage will never load unless I am logged in as a user.