XML Sitemap Last Modified Date on a View The site I am working on has a front page gallery view. 

Is there any way to update the last modified date of the view in the XMLSitemap file? As currently it is just empty.
The short answer is: No.

How are you including the views in the sitemap? I assume that you are just putting in custom paths? Without writing custom code, the only thing you can do for the custom path is to change the change frequency to a realistic amount. Don't exaggerate the frequency too much, or crawlers will start ignoring it.