Have a look in the link you send yourself:
http://www.asx.com.au/asxpdf/20160512/pdf/437655rxgtng2z.pdf
In the section "details of the option agreement" it has the 70% of Hawkmoth and the 90% of Arcadia just like on the web-site. So pretty sure/clear that current ownership is 70% of 90% = 63%.
Also the 51% clause of Zimbabwe seems to be true, so very likely Favic will have to own 51% when they go into production, is a law in Zimbabwe. So future ownership likely to be only 49% of 90% = 44%.
In fact I think that the missing 10% of Arcadia are also owned by Favic. Because if not they would own only 51% of 90%, being 46%. But could also be that 10% is owned by the state and does not count for the 51% rule.
