But I have a camera now! After the disappointment with the Pocketbeagle's built-in power-management system I decided to just hack my own Solar Pi Platter to act as a battery charger, power supply, RTC and USB Hub and then 3D printed a case. After a lot of spray painting I now have a brick of a camera!
This is a quick update. In case anyone is interested I will shortly update github with the schematic, new code for the Pi Platter and the OpenSCAD/STL files for the enclosure. Currently it's just running the existing PRU code ported to the Pocketbeagle.
I had one huge panic. I was manipulating the PCBs and bumped the Lepton on the desk. The shutter came apart and I almost did too. Fortunately I didn't lose any small parts. But it didn't go back together in a functional state. The shutter stuck whenever it closed. After contemplating another $300 I started hacking. Finally removing an internal shield and taping the whole thing back together yielded a functional part again. At least for now.