A few points need to be covered here. Firstly the aircraft did not lose an engine shortly after departure. There are some reports of an anomalous indication, but with all other parameters normal. That's not uncommon, and is normally an indication fault. For instance, if the oil pressure display disappeared, but the temperature remained normal, then there is no 'secondary indication', and it's just an indication fault. Pretty well everything that happens in an engine affects something else, so a single reading is always suspect (not ignored, just suspect).
There are reports that an engine stalled (at top of descent) and was shutdown (to recover from the stall), and it was the one running at idle. I would not, in any circumstances, trust that engine. So, it may have been running, but...
Stuck throttle at 70%. That's an interesting number, as it doesn't correspond to anything in particular. It's less power than the cruise. It may have been a setting at an intermediate point on the descent. Curious anyway. I haven't flown the 330, so I'm extrapolating from the 767...it may have been enough power to fly level, at low altitude and clean. I think it would be slightly above the power level required on a single engine approach. You immediately have major speed control issues if that is the case, as the a/c is simply going to accelerate on you, all the way down the glide slope.
If, on the other hand, that power level was insufficient for the approach, you have a modified glider, and your problems are even worse. In neither case do you have a go around option.
Evacuation. This is purely the Captain's call. You WILL injure people. Most will be minor, but there will likely be some very serious injuries. So, weigh that off against what you know has happened, and what you are being told. You also know that the aircraft is actually tested with a major brake fire, and left standing for 5 minutes before any fire crew action, so you have some minutes to decide. The tyres deflating is not an issue, though it will be violent, and the passengers are probably better off in the aircraft whilst that is happening. If you must have a fire on the ground, the wheels are probably the most benign point on the aircraft. In most cases, you simply won't have put enough energy into them to do anything other than deflate the tyres. You will evacuate when you have some other sort of problem. An engine fire that you can't control. A cabin fire. Perhaps a cargo fire. Generally though, you want some sort of confirmation, be it from the cabin, an external source, or your instruments.
In this case though, the landing was apparently at quite extreme speeds. The crew would know that they have put an enormous amount of heat into the braking system. I see it as a fair call either way.
It is a difficult decision, and it is one that the armchair critics always play with afterwards. Of course, they aren't sitting there in a lather of sweat, so mentally exhausted that they can hardly move.
From what I see of this event, it was extremely difficult, exceedingly well handled, and a huge credit to the crew. I might also add, that the various LCCs of the world, whilst claiming to be safe, simply give their crews the absolute minimum training. This was not something that minimum training would equip you for....
