Ah, starting then dying is different from a 'fried' ECU. In my limited experience, a failed jumpstart can damage the alternator or stop-start electrics. If the car starts, then the immobiliser is working. And the ECU is also permitting a start. And you have fuel and ignition working, so we're way ahead in terms of logical fault-finding. Keeping the engine running is the challenge. I think you're jumping to conclusions that the ECU is at fault, when it is much more likely that it is a simpler, easier problem to solve.
In order, my thoughts about possible culprits are:
1. Fuel pressure (I.e blocked filter, dead pump or pressure regulator)
2. Air Leak (I have come across a car with the inlet trunking disconnected that did exactly the same).
3. Sensor failure (in particular, a failed Coolant temperature sensor would cause this effect) I would connect a code reader (the port is behind a little removable panel in the front centre console). Have a look at the live data and make sure all the sensors have plausible data. For example, inlet manifold pressure, coolant temperature etc. You might hit the jackpot and find some codes that will indicate the source of the issue. You can get a simple reader for £35.
On Board Diagnostics (OBD) became mandatory for petrol cars from 2001 onwards. The clocks are connected by a couple of large connectors on the rear of the unit. Access is a click panel and 2 bolts. There are some online videos out there that show you the simple process of removal. Have a look at this?
Good luck!