The source code is for the PC app. The FW files are hex files only, not source code. These are NOT enough to make a new PPK2 as there are features not part of this FW that are needed to make a PPK2. This information is also unique for each device so you need to run a full calibration run with specific test equipment to make it work.
Long explanation for no, it is not possible to build a PPK2 clone at home..
