Error 9 is somewhat related to dropped connection.
There is more than one cause that can lead to this failure.
However, if the iPhone was charging normally before, does not have a charging port clogged with pocket lint, and was dropped (causing the screen to break) and bent (or possibly sat on), then you may very likely have a board level failure.
Technically, you may have a failed connection between a component known as the eeprom, and the CPU of the iPhone.
There are 3 popular ways to repair this: #1 reballing the CPU, very risky, very difficult and expensive; #2 drilling the CPU and placing "jumpers" to connect the CPU to the eeprom (risky, difficult, and expensive); #3 heating the CPU and applying pressure at the corner of the CPU where this failure occurs (very risky, could be only a temporary solution, can be cheaper).
Personally, my recommendation would be either to find someone who can offer you a no-fix-no-fee solution consisting of going over a few possible causes such as charging port, Tristar, NAND and NAND voltages, and finally option #2 = drilling the CPU (provided the cost is reasonable for both you and the technician performing the repair), OR discard it and buy a new (or used) phone. We've done option #2 before to retrieve data and were successful most of the times, and the most of those repairs lasted an acceptable amount of time afterwards.