Why is my keyboard not working? Trackpad still does

Recently, I decided to gut my Mac and upgrade the specs to suit my needs a little better. I replaced the logic board, the SSD, the fan, and the battery. First battery was DOA. Fast forward to the second battery, I plugged it in without installing it to make sure it was all good, everything worked great. The next day I installed the new battery, and put everything back together but the keyboard isn’t working anymore. I messed with the ribbon a little more (the keyboard one, not trackpad) but that didn’t seem to help. The power button works, I can boot into recovery, I’ve reset the nvram and SMC to no avail, but that means the keystrokes are registering. However, as soon as the login screen shows up, nothing works. Caps lock won’t light up, but the power button still works. I’ve tried repairing the disk, it says it’s fine. I’ve tried booting while pressing D but it never boots up. I don’t have an external keyboard to test but at this point I’m wondering if it’s software related or not. I’m becoming very frustrated as it’s my work computer and I didn’t foresee all these setbacks. UPDATE: I made the mistake of pulling the trackpad ribbon cable and reinserting in while the laptop was on and smoke started coming out of the trackpad so I think it might be time to take it to a repair shop at this point. Hoping I didn’t burn something on the logic board as well.