This question asks if Chess960 is really Chess960 and not Chess959, i.e. the dice are really not re-rolled (positive, instead of normative). The answer is yes, it really is.
However, why is Chess960 used over Chess959? (This is normative, instead of positive.)
Personally. I encountered this only once (and I remember the castling fail was funny). But in general, anyone playing this more than 959 times is expected to encounter this once. I believe the point of 960 is to get rid of openings. But technically it, ostensibly, doesn't (but of course, it does with at least 99.895833333% accuracy). Please explain what's going on.
My guess: Fun. Trolling players.