Why is my MONTH view still showing a DAY as the title?
It appears that the fix isn't in the latest release (7.x-2.8) yet and is instead in the current (7.x-2.x-dev) version. According to the comment #70 in that thread you posted, the patch is meant to be applied to the current release and not the latest dev (which is why it failed). If you run the patch in comment 70 against your 7.x-2.8 version it should correct the issue. As you stated that isn't an option, you can try to have the drupal update page grab the latest dev.

You can always check the release date for different branches on the project page. For example, Date currently shows the 7.x-2.8 branch as having been released on July 29th, 2014 while the latest commit, 7.x-2.x-dev, was released on June 16th, 2014. Hope that helps