TL;DR: if your Argon One isn’t booting, try trimming the IR receiver leads on the fan/power board.
Sharing in case it’ll help someone else in the future: when I installed my Pi 4 in the Argon One case, my board would not power on. Plugging directly into the Pi’s USB-C port worked, but when plugged into the Argon One USB-C port, no boot. Swapping between different power supplies, switching the jumper, and pressing the power button had no effect.
Best_Chain_4328 on reddit figured this out: if the IR receiver leads contact the aluminum case, there can be a short when the grounded Ethernet port casing of the Pi makes contact. The solution is to trim these leads. Once I did, the Pi successfully booted inside the case.
(Best_Chain_4328’s photo, not mine):
