'If' they had been following normal Company policy and had been carrying minimum fuel then by the time they were making the second diversion to BHX they would be well into their final reserve fuel.
It is not normal company policy to carry minimum fuel. Fuel was not an issue in this accident.
And again, they were not sacked. All parties involved agreed that any continued cooperation would be very difficult. The crew involved chose to have their contract terminated by the company, as that was financially the best option for them.