1) The 'position' of cockpit controls is of relatively little value when there is an FDR trace. Several of us have cautioned about 'running away' with these pieces of information. Those who have seen cockpits after relatively high-speed impacts will know what I mean. Only where there is no FDR reading of throttle position on the runway will witness marks etc be relevant.
2) I also suspect that Veja has polled PPRune and elsewhere and made an 'intelligent' guess at this. Whether or not there has been a leak we will discover eventually. At this stage the article really provides only peripheral interest.
3) Without either second-guessing the cause/s of this accident, nor honestly trying to start an anti AB campaign, I sincerely hope that AB and the training system for AB are looking at the throttle lever function. I'm sure it is very clever and no doubt there are technological advantages to the way it works. The BIG problem is that it is not 'NATURAL' in terms of around 100 years of powered flight where the engine and the throttle lever are effectively directly linked, and furthermore it seems to be confusing judging by the different opinions we see here from supposedly qualified AB crews. All the clever graphs, pdf files and studies on landing risks and runway state etc go flying out of the window if this happens.
With some time on the 737, I am not aware of any 737 incident where the throttle/s may not have been closed on landing other than, perhaps, in early training days. If anyone knows different then there are bigger issues at stake than just the AB system.