I wish people would actuall look at the checklist as it was at the time before they spout nonsense like "big fat warning - stupid pilots".
This is what it looked like at the time:
< normal starting engine stuff >
WARNING
If the oil pressure has not moved from the red range within
3 seconds after starting, set the ENGINE MASTER switch
to OFF and investigate problem. When starting the cold
engine, the oil pressure can be as high as 6.5 bar for a
maximum of 20 seconds
10. Circuit breakers.................. check all in / as required
11. Idle RPM........................... check, 900 +-20 RPM
12. External Power................... disconnect
13. Opposite engie................... Start with normal procedure
14. Warm up .......................... IDLE for 2 minutes / thereafter 1400 RPM
END OF CHECKLIST
So yes, it is clear that the other engine should be started normally, and yes, following this procedure would have (probably) prevented the accident (assuming the drain of the glow plug / starter motor would have caused the voltage to drop sufficiently).
But from the above it is pretty clear that no-one did see that one coming, and the procedure was not designed to catch that error. Just look at the WARNIG about oil pressure (which might cost you an engine) and not a single peep on the risk of engine failure on gear retraction (which probably costs you the airframe and perhaps your life).