Hi,
I wish I had seen this sooner, I would have fixed it for the 2.3.2.9 release.
However, I think you can work around it.
In your layout.master, manually add the correct stylesheet link for your local copy of YUI.
Then to prevent the mojo code form adding the google cdn version, add this also in the <head></head> section:
<asp:Literal id="yui-datatable" runat="server" Text=" " />
The code will see this and think the css is already loaded.
I will fix this for the next release.
Hope it helps,
Joe