It seems as if the wireless module somehow prohibits the PowerDelivery negotiation between a USB-C charger and pocket if using a USB-C-to-USB-C cable whereas pretty much any USB-A-to-USB-C cable seems to work.

Reiska is absolutely right. The wireless module is not negotiating power correctly and will not pass through power from any PD or "smart" chargers.  The cable doesn't matter as much as the charging block.   I have some Anker chargers that have "IQ" smart charging on the USB-A ports and a USB-A/USB-C cord from there will not pass through the wireless module.  The same cord works fine passing through power from a "dumb" charging block USB-A port.  
Here's my guide to getting power to pass through:
Don't use USB-C to USB-C cables.  By definition they plug into sockets that implement power delivery (PD)
Use a USB-A to USB-C cable.
Use a dumb power brick.  No PD, no "IQ" (Anker), no "Quick Charge" (Qualcomm), or a handful of other smart charging names from other manufacturers.

Remember, this is just for getting the pass through to work on the wireless module.  If you take the wireless module off and plug directly into your OSMO Pocket, any of these smart charging systems work fine

BobWinNV has it right. Contrary to what Mindy is saying, it has nothing to do with the quality of the cable, the tenth of the cable or the power of the charger. It simply requires the use of any USB A to USB C cable, because the port on the wireless charger is not a real USB C port.

My OP normally charges even through the wireless adapter using the original OP cable, But lately I noticed that theOP does not charge anymore through the wireless wi fi  adapter, I remove the wireless wi fi adapter and directly charge the OP using the same cable and noticed that the battery level increased, My analysis is my OP is charging using the supplied cable, Question now is why  does the wireless adapter stop charging my OP although the wireless connection is still working and can be connected in my Phone

daniel.davis.wa@gmail.com Posted at 2020-8-25 10:26
Reiska is absolutely right. The wireless module is not negotiating power correctly and will not pass through power from any PD or "smart" chargers.  The cable doesn't matter as much as the charging block.   I have some Anker chargers that have "IQ" smart charging on the USB-A ports and a USB-A/USB-C cord from there will not pass through the wireless module.  The same cord works fine passing through power from a "dumb" charging block USB-A port.  
Here's my guide to getting power to pass through:
Don't use USB-C to USB-C cables.  By definition they plug into sockets that implement power delivery (PD)

Wow, thank you all for clearing this up. Being a good little tech nerd, I use smart chargers for everything, so NOTHING seemed to work with the wireless module!

Now I need to look in the junk drawer for the dumbest charger I can find!

Haven't really looked through this entire thread. However, note that whatever cable you use, DJI recommends a 2.4-volt charger.

This is very old now, which is why I am wondering if the FW update ever came out to support C cable charging via base?
I can't see anywhere what the "current" version of FW is.  There's no updates via app, so I guess this just never got done... very disappointing...