Latitude e6400 after repair keyboard won't register

Hi. I spilled a bit of water on my Latitude e6400 touchpad which rendered it dead. So I took from an older (same model and specs) base and switched out the touchpad and palmrest. I wound-up forgetting that base top/cover (where it hinges) had been broken and so I had to separate touchpad from palmrest to fix it. I now have a wonderful working touchpad but my keyboard doesn't work. I ran a BIOS diagnostic and it says things are fine. It does say though on backlit keyboard option: no. Does that mean the keyboard isn't registering?

Some facts about the (failed) repair:

The first diagnostic I ran said the touchpad cable wasn't present. I fixed that.

I looked at both complete laptops and the only potential, possible difference I see is on where you hook up the burnt orange semi-see-through cable on my working one the cable goes above the little gold pins and on the failedfix then seem to go under the pins. I tried to make it so they looked the same but the burnt orange cable (goes under the rainbow touchpad cable) seems to be a bit longer on one computer than the other. If this is my issue though, I will get my more dexterous fingered brother to put the cable in. My hands are a bit damaged and so I acknowledge it could be me. Before going to that point though I would really appreciate an opinion if the cable could be the issue or if I jacked my motherboard.

Oh, a USB keyboard does work.

I'm aware I might seem a bit dumb but I am genuinely doing the best I can and learning with videos and tutorials online so I'd really appreciate some opinions/advice.

Thanks for reading.