In November 2015, Twitter made the decision to remove the ability to see the Twitter share count for your content.
Similarly, Google+ removed the ability to see share counts for your content in 2017.
When these changes went live, it affected any service which relied on pulling the share count directly from those services, Sumo included. This is why you are seeing 0 Twitter and Google+ shares in the Sumo Share app.
It's unfortunate that these share counts can no longer be tracked. Since these services removed the ability to look them up, the numbers are no longer available for us to provide to you.