Jay:
I'm going to Rio just after New Year's. An acquaintance of mine is on the board at Gavea, and they've asked me to come look at the course to see if there is anything which could be done to make it Olympics-worthy, or whether they should even try. The course is famously short, so it's pretty unlikely the event will wind up there, but they do have the right connections.
I will see what else I can find out when I'm down there. But, if I were the Rio organizers, I would just sit back and see what various developers offer to build for me, instead of committing to a site right away.