Therefore I can only presume you are both trying to use the same querystring admin=stats to show the main plugin page.
As I mentioned in the original thread, I was able to install WP-O-Matic on one of my test sites, and everything was working properly. You might want to look at the changes you've made to the plugin on your end, since the original plugin seems to be working properly with Jetpack Stats.
Feel free to post again in the original thread if you find a solution!