What are the usual suspects? I would expect the PSU? I took some images
https://imgur.com/a/CJiLIpA

It is definitely pushed in all the way, and I can drag the board across the table with the cord. Cable is snug.

I've tried ripping everything out and plugging in just USB, and 3 different computers with a known good data enabled cord.

After discovering that the WiFi server was down and the controller was no longer connected to WiFi by checking my router, I plugged the board into a computer and the board never came up in device manager.
the 3.3V, 5V, diag, and the led between the reset button and the USB plug are all on, as well as V in when connected to the PSU. The end-stops and IR probe still function. and no components (the processor, the 3.3V regulator U2, the small 14-pin ICs or the WiFi module) get hot after prolonged power on through USB or 12V.
I have been through the steps listed here: https://duet3d.dozuki.com/Wiki/What_to_do_if_your_Duet_won't_respond#Section_Connect_to_a_PC_via_USB_and_look_for_the_port and the erase and reset buttons have no affect.
At this point, I have no idea what happened or how to prevent it

I have. There are 3 red LEDs (diag, 5v, and the one betwwen the usb prot and the reset switch) and the green 3.3v LED that are on. No ports appear, even after using different USB cables, USB ports, computers, or attempting to erase the firmware.

I left it plugged in for 10 minutes and the only thing that is hot is the WiFi module

My Duet WiFi is no longer being detected by USB across multiple computers, ports, and cables.

The only symptoms I have are 3.3v LED, 5v LED, the LEDs next to the micro USB port, and the WiFi adapter gets fairly hot when plugged into 5v.

Right before this, I was leveling my bed with the mini Ir sensor when the cables came loose and I didn't notice so my head crashed. I did an emergency restart and the board wouldn't connect to WiFi anymore.
I then connected it USB and try to re-setup WiFi. When doing that, the board said it couldn't start WiFi.
So I went to update the firmware, and I noticed there wasn't a firmware file on the SD card. After I uploaded that file, I'm where I am now. The Erase and Reset buttons don't seem to do anything.