I agree I think it was 80% KLM 20% the other two.
I would have a hard time giving any blame to the other crew aside from being in the wrong place at the wrong time and not being able to see the taxiway. There's a documentary on this tragedy, and, going by what was explained, there are a few things to note:
The KLM captain was trying to not let too much time pass, thereby grounding his crew and putting the passengers up in a hotel.
He took on a full compliment of fuel for the NEXT leg of his flight, reducing the turnaround time when he got to land at the intended destination.
He attempted to takeoff without a clearance from the tower and at least once was stopped by his own first officer.
He knew that there was another aircraft on the runway, as was told to him by the tower, the other crew and his own crew, and yet decided, on his own, that they must be off the runway and therefore it was clear and time to go.
He knew that due to the large amount of traffic that had been diverted there, that the taxiways were blocked and full of airplanes, the ramp was full of planes and it was foggy.
I'm not trying to blame a dead man, but I am trying to NOT blame another dead man.