New 3DS doesn't turn on or charge, no lights :(

[moonlitDee]

I had a New 3DS that would shut off when slightly shaken. I thought that was a screen ribbon issue, so after some disassembly and reassembly, I was surprised to see it worked even less than before.
No lights, not even the charge light. (The charger works, tested with a DSi XL)
The possible culprits I can gather from looking at what I'd done are
1) The IR sensor. Its ribbon cable got to the point I could no longer fit it in the connector, so it stayed disconnected.
2) The ZIF connectors. I hadn't realized they didn't need unlocking to remove the ribbons, so I could've broken them.
3) The daughter board ribbon, or rather its connector. I can't fit a new ribbon into the connector, it's like it doesn't fit. (Motherboard side)
4) I might have just scratched the PCB or done some other mechanical damage to it, I don't quite remember.
If anyone knows what could be the problem, I would really appreciate any information. It can't really get worse than how it already is, so if there's something I should try, I will. (Except anything involving buying or soldering anything, I'm broke and have just graduated high school, plus my soldering iron sucks.)