Well Panda you have to conisder a few things, no one disagrees that the landing was not conducted well, but....
They were not on Arusha Frequency, which makes me wonder if they even knew where they were, after landing pilots apparently asked what the name of the airfield was.
Arusha alarm was sounded as the aircraft came in over the threshold, so pretty sure the tower had no prior warning.
Considering the proximity of the parking apron to the runway it is very fortunate that none of the ATR's that usually are there at that time were there, otherwise there would have been considerably more carnage.
Once safely landed, why did the pilot attempt to turn? There is no where for that aircraft to go, no turn pad and from the cockpit you can see only grass, I'm guessing they might have been in a bit of shock after such a tight and dangerous landing and rightfully so not had their full faculties about them.
Even with a partially blocked runway it would still have been safer to land in Kili, perhaps as 737 lover said earlier it is a case of mistaken identity as both runways are orientated the same direction. Also Mount Meru is next to Arusha and to the unfamiliar might be mistaken for Kilimanjaro.
I'd like to hear the radio conversation or even better the cockpit recordings as to how they decided to go to Arusha. An airfield that small would not even be in their on board database.
The report of this incident will make for some interesting reading, also wondering if the aircraft will ever leave, it looks like an old ex Charter bird, probably leased hence no colors, might not even have an Ethiopian interior, I know KQ used a few a few years back. The owners might just cut their losses and strip it of everything that is useful and leave it there.