The Ubuntu project & community does not take responsibility for PPA and their packages. The only packages that the Ubuntu community maintains are the ones found in the main, restricted, universe and multiverse repository.
Most of the times, there is no way to use Ubuntu standard tools (like Apport) to report bugs against non-Ubuntu packages. You have just two options when you find a bug in a package provided by a PPA:
If you think the bug is also in the Ubuntu "official" package, then remove the PPA package and test the Ubuntu package. If the bug can be reproduced, use ubuntu-bug to report it.
If the bug is only in the PPA package, you should get in touch with the maintainer(s) of the PPA. They will give you instructions about how to report the bug.