The fates intervened in the form of the G3 flight from BEL-GRU having a mechanical diversion to BSB. The details were given in Portuguese so it wasn't until after we were on the alternative flight that we found out the other flight had been flying on 1 engine from the new crew. We had been on a weird schedule due to the award availabliity on AA and max 24 hour connection rule which actually had us going BEL-GIG-GRU and the following day GRU-SCL with conx to QF back to SYD, then BNE. Due to the irrops, we would have missed the GIG conx which we didn't really want but AA had booked us on. Upon arrival in GRU on a different plane, the G3 staff gave us free accommodation in the Matiz Hotel with transfers provided by the hotel and all meals until time for the GRU (EZE) SCL flight. So no Ibis or Fast Sleep needed and I won't be able to comment on either one. The Matiz Hotel was fine, free internet and plenty of food thanks to G3 paying for it! The next morning after breakfast, we took the bus 552 from the nearby bus depot to Armenia metro station, then used the metro to get to the zoo and Praca da Republica to visit the craft market.