Part of what stinks about this ANZ/David Hisco mess is that a lot of it is shrouded in mystery.

And when there's mystery, there are more questions, and when there are more questions than answers, that's when the rumours start.

The key to strong leadership is to be transparent and open, to lay the facts out straight, to be upfront. An institution like the ANZ bank should know more than anyone about the ins and outs of good PR.

Good PR means fronting up. It also means being clear, and not leaving details to the rumour mill. The other thing the ANZ should know is that banks are usually public enemy number one - it doesn't take much for a bank to do wrong, to get people's backs up.

ANZ should also be aware, off the back of Australia's Royal Commission, that people are already wary and suspicious of banks: the level of tolerance for indiscretion is thin.

So from ANZ's apparent 'upfront' disclosure on Hisco, comes a series of questions not yet answered.

• Why is he not repaying the estimated $50,000 spent in personal expenses? 
  • Why so long on sick leave, was it really sick leave? 
  • What was going on in the lead up to this behind the scenes and how long and how much did the board know?
  • Did Hisco have a 'verbal agreement' for spending on chauffeurs and wine storage? 
  • How much did board chairman John Key know and for how long? 
  • What processes does ANZ have in place to prevent this kind of thing happening again? 
  • Why is Hisco forfeiting all of his ANZ equity holdings? $6.4 million is a high price to pay for indiscretions amounting to only tens of thousands of dollars over nine years. 
  • And why did John Key throw a junior staffer under the bus?
  • Hisco maintains his innocence – so, will he be taking legal action over this?

On top of all the questions and rumours, we have the outrage of the union members. 
That part was predictable - it's never going to play well with worker bees on the shop floor that the CEO is swanning around to and from his wine storage in a chauffeured car.

Which leads me to the other question: was it a private chauffeured car or just a Corporate Cab?

No one seems to have clarified that either way yet either.

So a head has rolled, but the whole debacle is still shrouded in a lot of mystery.

Just to muddy the waters further, Winston Peters wades into it yesterday suggesting he knows more than anyone else, that there's more to it. Knowing Peters, that may or may not be the case, and he won't care either way. Usually he just likes stirring the pot.

But for ANZ, this whole sorry saga looks like a mess they haven't really done a great job of cleaning up. Which leaves the sinking feeling that there's more to come.