Yes... Sorry it took so long
The answer lies with the theme.
I see the theme is "score" from ThemeForest. The integrated widgets don't generate the "hreview-aggregate" class required by Google for rich snippets.
If you look on the theme demo page source code you'll see the hreview-aggregate class is missing there as well.
As this is a commercial theme - I'd approach the developers to include the class. It's strange they haven't as the theme is advertised being intended for GD Star Ratings.
There's also a few issues with BuddyPress and GD Star ratings
You may be able to write a custom function to pull the aggregate - see this thread for more info and an idea for the code - Display average of a multiple rating in loop The code MAY need modding to work with the theme.
Then enclose the result in the required class.
Also note - the standard GD Star "Blog Rating" and the multi-article "Star Rating" widget also don't generate the class. That's not a bug - rich snippet star ratings can only apply to a single article.