I think the asset write downs could be related to the financing solution, and the financing covenants. There is possibly one about net assets, or the fluctuation in net assets - so it is prudent to write down prior to reaching financial close.
Having said that, I do think ID is the most overpaid person on this planet and has a lot to answer for (and certainly a breach in trust - it shouldnt take financing covenants to bring out write downs)...
We are now into month 2 of FY19 and still have no idea about the capex outlook for FY19.... (or the expected well run rates that he promised)