I think that the whole South African Olympic Teams for all disciplines were to be announced on June 7th. The South African Equestrian NF set their selection date to back on May 23rd, IIRC, so (they said) all of the administrative approvals could come from the Olympic Committee and their team announced with the others. Peternell was not qualified in May; he qualified at Brabham which finished June 9th.
Problem per CAS is that he was not informed of the earlier closing date; and the South African criteria were clear that the rider with the most Olympic rider points had to be chosen if he had a qualified horse that could go.
Both AP Uprising and Tiger Eye were injured and not available for the Olympics at the time of selection.
You should read the CAS arbitration opinion.
When I said “funny”, I meant “funny peculiar” not “funny ha ha”.