I’d like more information on where you state:
> Launchpad is released under the GPLv3 license, which means you’re free to use Launchpad in commercial projects and to build off of the code as much you want to. I have, however, added a gentleman’s clause to it.
That page mentions nothing about an addition clause but does state right at the top of the GPL explanation that modification of the GPL is not allowed (and honestly getting a legal department to approve a GPL thing is hard enough - even for my tiny company a modified GPL is pretty much a non-starter where a regular GPL may be fine depending on use case)