Are you sure its the injector drivers and not a wiring or injector fault?
Eliminate that possiblity first, a simple test would be to unbolt the injector rail and tumble the engine and see which injectors are firing, then swap plugs from 2 & 4 onto 1 & 3 injectors, and tumble again this will prove the injectors.
To verify the wiring a DVM would be handy to check continuity from the injector plugs to the ecu harness plug also each injector plug should have 12V constant on one terminal with the ignition on.
It's best to use a small bulb like 5~ 15 W to test this as it puts a load on the circuit, so ground one leg of the bulb and test each plug for the 12v.
I would also test each injector for its resistance, should be about 14 ohms.
The daughter board can be transferred to another of the same type ecu.
So if its B14 another B14, P10 ecu is like the B13 ecus but I think after 93 there was a different ecu in the P10, I am not fully knowledgable about the USDM ecus.
Any electronics repair shop or someone with good soldering skills can transfer the board.
Also there is one jumper that has to be moved on the main ecu board itself this tells the ecu to use the daughterboard instead of the internal rom. Any of the calum installation or nistune installation write ups will apply.