This sounds interesting! I am currently without a fully-functioning development box (as explained on the agrip.org.uk
website, just updated today) but I can say that if you are able to download and compile the 'vanilla' audio quake code from GitHub, then you will get, as part of that, the programs required to compile QuakeC code, namely ZQCC, the QuakeC compiler.
In the latest beta, we have got some of the documentation back; I am still working on updating this, including the development documentation and will resume doing so ASAP when the computer is fully functional again.
Please let us know if you have any questions/problems getting hold of that and getting it going. The instructions for building a release were tested recently so should be good -- it's the detailed development manual that is yet to be updated; it contains info about how the germicide and engine work together and how to structure a mod. Though of course you have both 'vanilla' AQ and JediQuake to learn from too.
Thanks and best regards,