My question is inspired by this question
Basically instead of the Earth being a planet it is instead a small portion of an Alderson Disk. According to the writer Larry Niven "an Alderson disk would be a wonderful place to stage a Gothic or swords-and-sorcery novel."
Assume that for all intents and purposes climate and everything on "flat Earth" remains the same as on the planet Earth. However the Americas are located to the east of Asia, and to the west of Europe is a huge continent which is populated by fantasy races.
Assume that all of human history is the same until Columbus's voyage in 1492 where he lands just off the coast of this continent and finds that it is populated by fantasy races. These races are in fact just alternative humanoid evolutions, descended from Homo Erectus or Australopithecus. The three races are elves, dwarves, and orcs.
The elves are split up into multiple nations, having technological levels similar to Native Americans, ranging from the Carib tribes to Mayan civilization. However these elves also have some amount of light magic such as hypnosis, telepathy, mind control, remote viewing, telekinesis, and limited elemental bending.
The dwarves are also split up into multiple nations, having steampunk technological levels, going through an industrial revolution, but no magic. They mostly keep to themselves, living mainly in and around a network of natural caves and lava tubes containing rich mineral deposits. They have sophisticated railroad like transportations that goes under the ground through the lava tubes, and underground cities like Cappadocia but having elevators, electricity, water plumbing, and ventilation. Their main activities are mining, engineering, and trade.
The orcs are mostly united under a single empire, having technological levels similar to ancient Greece. The empire is highly militaristic, xenophobic, and religious fanatical, with an ideology similar to Nazi Germany. All non-orcs are considered as inferior races, therefore killing them and taking over their land is considered a virtuous deed. The orc empire has a greater territory and manpower than the Roman Empire, fighting a continental scale war on several fronts against the dwarves, elves, and rebel orcs. The empire also has internal social problems such as extreme corruption, conspiracy theories, extreme social inequality, brainwashing the citizens, and a heavy handed political police.
This is the "new world" which is discovered by Columbus and his men. My question is, how would Europeans react to the discovery of such a world, populated by humanoid races who are not strictly speaking Homo Sapiens? Would they be shocked, disbelief, or ridicule Columbus? How would the Spanish government react, and would they send conquistadors to help one of the factions in the war, and which faction would they join? Would they try to colonize this continent? What about other European countries and the Arabs or Ottomans?