I did not say it was DD, as you rightly say he would have had to...

I did not say it was DD, as you rightly say he would have had to declare any trades or make an announcement to the ASX. However, good or bad news has a habit of being heard or suspected by the professionals who make a living out of assessing rumours and distilling fact from fiction and it is quite possible that "someone" heard from some source that DD was interested in (say) expanding his car interests in NZ and looking to free up some cash to do so. I live near Cromwell in New Zealand and it is not beyond the bounds of possibilities that someone here has heard some gossip and put 2 and 2 together..........
I see enough dramatic share price movements on the ASX and NZX shortly before good/bad news is announced to support the commonly held belief that 'word gets around' before any official announcement has to be made.