In retrospect it would have been easier for you to transfer the serial flash memory at U12 from patient to donor.
Anyway, you have verified the presence of the Vio supply (+3.3V), Vcore (+1.3V), and the negative preamp supply (-5V). Since these are controlled by the motor controller IC, then your soldering must have been successful at least in part. However, I would confirm the voltage at the output of the Vcore regulator, at the junction of the R050 resistor and the two filter capacitors, C3 and C4.
Do you see any activity (“spin buzz”) at the motor terminals during power-up?
Sorry, I was referring to a similar circuit. In your case there are two capacitors and a resistor to the left of L1 in your photo. These components, together with D3 and Q1, constitute a buck regulator that generates the Vcore supply for the MCU. If the MCU were shorted, for example, then the resistor may be open circuit.
The location of the burn mark on the original motor controller might shine some light on the nature of the fault. Was the mark on the motor side of the chip or on the regulator side?