Hi Matt
Our setup is not quite how you mention above.
We have 1 lot of FTP space / webspace. Within this webspace is our website and blog, in the following configuration:
ourdomain.com/ – main website run using Joomla
ourdomain.com/blog/ – blog site run using WordPress
The homepage to our blog, is a list of blog posts using excerpts. We do not have a static page as our homepage on the blog – we have our Joomla based website for that. Each part of our website has its own database.
I have checked in my test environment and i have both the “hompage” and “excerpts” tickboxes enabled on the Advanced tab within the AddThis settings. If i disable the “homepage” option it makes no difference, the AddThis icons still don’t appear.