RESOLVED:
As as similar issue was brought up by another dev, I revisited my device and I’m embarrassed to admit that the reason I was having this issue is that my actual device’s wiring did not match the wiring in my diagram above. Fixing the discrepancy fixed my device and it now works as I intended.
(To be totally transparent, though again I’m super embarrassed about it, I wired the ground to Pin 1 instead of Pin 40 by accident. I must have been tired or something, idk how I messed up that bad)
Anyone else having similar problems should A) triple check that their wiring is correct, or B) troubleshoot your hardware, I suppose?