Google+ Snippet with Open Graph Protocol
I think that question is similar to Generating Open Graph meta tags dynamically. The main reason of your problem is that google+ and facebook will not execute your javascript so none of them will see your dynamic og tags.
Basic solution to this problem is :
- create unique url for each dynamic page and save dynamic params for this url into database.
- when your user try to share pages with this unique url you will find saved dynamic params
- create page with og tags filled with found dynamic params
Use server side scripting (ask for details in the comments)