When the treacherous guide is impaled on the spikes in the cave and Harrison Ford reacts with a shudder and a breath, he says: "Adios, Sapiro." According to the script, Alfred Molina's character is named Satipo! Could it be that Mr Ford got too much of a fright?
I beleve Indy is making a joke. Instead of saying "Adios, Satipo", he says "Adios, Stupido" because Satipo was so dumb to set of the very trap Indy pointed out to him just minutes earlier.
No, he definitely does say "Adios, Sapiro" without mumbling or saying anything else, but I think that this slipup of mine is going to join Mark Hamill's supposed shouting of "Carrie!" to Princess Leia in Star Wars IV ~ A New Hope.