When opening any of the web browser-based apps (ex: Google News or Facebook) from the homescreen, you are prompted to select which web browser to open it in (Chrome, Lightning, or WebView). After selecting any one of them, the URL (these aren't really the actual Android apps, they're just opening in a web browser) opens fine. However, it doesn't retain your browser selection the next time you use that app, and I don't see any way to specify a default browser application. So every time any of these browser-based apps is opened, the OS is going to prompt you for which browser to open it with.
Actually, it would probably be a better UX to simply remove Lighting and WebView browsers from these tablets and only leave Google Chrome. If there were only one web browser available on the device that would probably solve the "which one do you want to use" prompt. Also, Google Chrome has a much better UI and looks more like a standalone app. Whereas the other two literally open a new tab in a web browser. And also, unless you intentionally close tabs, it's going to keep opening new tabs each time you open one of these apps, and you'll have 20 browser tabs across the top of your screen.