Based loosely on this article and the mostly useless Metro configuration docs ; the code was more useful.
In the root folder:
lerna bootstrap --hoist --nohoist=react-native
We need the nohoist option because we will invoke react native CLI from each folder and it will fail miserably otherwise.
This command will gather all the dependencies, except react-native to a single node_modules folder in the root of the project.
Now, you can go to either the packages/investify or the packages/whitelabel folders and run:
react-native run-android
In Windows, the metro cache is located at %appdata%\Local\Temp\metro-cache. Just delete that folder if you have a feeling your changes aren't reflected.