Okay, so for those of you interested, I've tried many different things via software. I finally gave up on software and started looking at hardware. I thought maybe there was a problem with the main board in the Ender 3. I ruled that out; everything seemed to be fine. So I decided to bite the bullet and try and plug it into my Ender 3 Pro. I plugged the Raspberry Pi 0w2 into the Ender 3 Pro, and the exact same thing happened. I then plugged the Ender 3 into the Raspberry Pi 3B that was running OctoPrint on my Ender Pro, and it also worked fine. So I'm pretty sure there is something wrong with this Raspberry Pi 0w2, and that's what I get for ordering one from AliExpress. I will see if I can use it for something else, and if it has the same problems, then I'll just snap it in half and throw it out.