On an Android device, the deep link URL does not always stick. It will regularly drop the "K2://.." from the hyperlinked deep link URL, resulting in it attempting to open a regular URL.
If you get the hyperlink to stick or inject it into a browser's URL, nothing happens. The same link will work on the iOS version of the Mobile app.
Android Deep-linking has not currently been implemented into the Android Mobile app. If you would like to see it added to the Android version soon, please add a feature request to https://ideas.k2.com/ to increase visibility and get the ball rolling faster. Please see the following release notes showing deep linking being added to iOS but not Android (in version 1.2.5, deep linking was added to the iOS app but has yet to be included in the Android version).