Data recovery professionals will rarely need to transfer an MCU from one PCB to another. The subject drive appears to be a “ROYL” model. These drives often store backup copies of the flash memory in a hidden System Area (SA) on the platters. The professionals simply install the replacement board and then access the SA using their diagnostic software. The “ROM” is then rebuilt and reprogrammed with a single click of the mouse. For this “data recovery” service, the user will be charged anything up to US$2000.
The following article shows how this is done using SalvationData’s HD Doctor.
Fix Identification Problem caused by Corruption of ATA Overlay module or ROM content:
In the OP’s case the DR pros could install a compatible SATA PCB and use it to retrieve the SA contents, or they could use their diagnostic tools to do the same thing via USB or via the 12-pin connector (depending on the tool).
In any case, reattaching a USB connector is a trivial job for a competent junior technician, so anyone who claims to be a DR pro should be able to handle it without difficulty. If you can’t resolder a USB connector, then you can forget trying to move an MCU.