They reproduced the incident. I would suspect it would take several tries to get it just right. The people doing the test did not believe it until they ran test with fuel tanks and recreated it. They also took a 747 up under the same conditions with temperature probes in the fuel tank.
Have you seen the documentary?
It is my understanding that the incident was NOT recreated, but ignition sources of higher energy were necessary to get a burn. To which documentary are you referring?