Needs a new charge port. If the port is soldered onto the board, i suggest getting a new tablet, however, most of the tablets use a flex with a charge port on it, try finding this flex/daughter board, but be careful, and make sure you bought the correct revision. If you could post pictures of your tablets motherboard (with just the back cover off) then i can tell you if the charge port is something that is soldered or is on a flex/daughter board.
These connections are considered pressure connections. I have had this happen on iPads before with new techs, and when that happens sometimes you can rig up something and sometimes you can't. What I did when new techs had this issue was place the tab back into place if i could, take some electrical tape and tape it in place (if you don't have this, then a tiny piece of paper (2 or 3 layers over the metal pins will work). I then would add a few more lays of tape so that when we screwed the LCD back in it would add pressure allowing the connection within the digitizer clip, sometimes i did not need to do this and it would just work without rigging something up. In your case add some lays of tape and then close the phone up and put in the bottom screws, you can keep the phone on while doing this, so you don't have to keep turning it off and back on while opening and closing it, just be very careful, then see if the proximity sensor and ear speaker work, these can be tested with a phone call, the proximity...
This is a broken LCD. You will need to take it to a repair shop where they will replace the entire assembly (digitizer, LCD, and glass) or order the part as an assembly (digitizer, LCD, and glass) and replace it yourself.
I say take it to the Apple Store and see what they say about it. They may just replace the phone. Also check if it has water damage by opening it up. If so make a complaint with eBay. And there is no serial number on the actual board. I didn't think there was on the 5, 5c or 5s either? If you take it to apple and they replace it I would make a mark on the board and take a picture of it then if you have it sent back again you know if it's yours or not.
For the 4 if the digitizer connection gets scratched or bent bad enough it can cause the screens digitizer to stop working properly. If the flex is okay check the pins like Sophia said to and if those seem good then the board may have be damaged sometimes during the repair.
Have you tried DFU mode? Also sometimes a new battery and/or charge port will fix this issue. Other times it may not. If you have not tried a Mac I recommend trying that as it can sometimes bypass the errors you get on a PC.
I have seen issues like this however it was cooking oils that spilled on the phone, but same concept. If i were you i would take the entire phone apart and clean the mother board off, taking any EMI shields off that you can manually, and look to see if any chips have oil on them, if so wipe them off, and i would also take the screen off and wipe down the back of the backlight, the oil will move around and can get into your backlight and then you will have light and dark spots on your screen. I would also check to see what the hair oil is made of, if it have any water in it i would also recommend buying at least 91% isopropyl alcohol which you can get at rite aid, pour a little bit of alcohol out onto a table or in a little up and use a tooth brush to dab it into the alcohol and then gently scrub the board. This will cause any water to evaporate. Also if you think it is necessary wipe down the inside of the phone with a paper towel that has some alcohol on it. Once dry put it back together and see if it...
This typically happens when you replace the power button.. 3rd party prox flex's/ambient light sensors do not always work properly once they replace the old one. Try covering the prox/ambient light sensor up half way right above the ear speaker when you take the screen off. If this does not work then the prox flex (which it is typically referred to as) may be defective.