Anyone who reads aviation accident reports quickly understands that most accidents evolve from a fateful sequence of circumstances and events which lead the participants to their fate. Those up front who share the consequences inevitably play some part in the chain of events.
What distinguishes these two pilots is that they broke the chain of bad luck, mistakes, carelessness, error, or whatever it was and, with considerable skill and really breathtaking coolness conducted that successful long glide to their hot landing on the runway at Lajes.
Sure it could have been better. Sure it could have been worse. The proof is the result - the passengers eventually reached their destination.
Like the rest of you, I don't know if the crew's decision process was right or wrong in managing the crossfeed, but I doubt they had any intention to do other than solve the problem confronting them in the best manner possible. They likely tried to use the best information that training, aircraft systems, and other resources could provide at the moment. If those resources failed - like the hardware - it was probably not primarily due to a character flaw on the crew's behalf, but to various defects in the suppport, training, and operations systems that were behind them.
Ultimately they did what pilots are really supposed to do: stay cool and focussed even when things have gotten way out of the
box; work the problem; steer past the adversity and put down as safely as possible. And they were lucky enough and skillful enough to get that part, the really important part, right.