After 5 min of trouble shooting, I figured it out! I was using Better Cut to create the maps icon on my home screen. I was doing so by choosing create new shortcut, activity, and then the maps activity. For some reason the ONLY maps activity you can choose in Better Cuts list of activities gives you the message "Unable to open the URL" every time you click the shortcut it creates!
To bypass this error while still utilizing Better Cut to create the shortcut, simply drag the stock maps icon out of the apps drawer onto your home screen. Then open Better Cut from the apps drawer and choose edit existing shortcut. No more annoying message! :icon_ banana: