Kristof had entered the Rhino Run in South Africa - although I see he is no longer on the list of starters.
It has just got postponed from this November to next year.
I think he got freaked out by Mike's death and the whole experience of the roads in Australia (maybe also the supporters too). He's a pretty private guy, doesn't go looking for attention, and only ever entered a race when one was organised almost past where he lived.
He did a low-key one, Diablo something or other, in France in the summer.