Puella Magi Madoka Magica and Fate/Grand Order Challenge

The challenge is this: Chaldea detects the Madoka Magica timeline and sends Ritsuka, Mash, and a team of Servants to investigate it. They could arrive sometime during the main series, hopefully before Mami is killed by Charlotte. They could arrive during the Rebellion movie (their arrival would penetrate the shield Kyubey put around Homura and they would appear inside Homura's Barrier), or they could arrive after the Rebellion movie. You could be daring and have them arrive during a different timeline like Magia Record: Puella Magi Madoka Magica Side Story. The point is that the Chaldea crew will change destiny since both Homura and Kyubey won't see them coming. The Magical Girls would be surprised by seeing people, especially males, with powers without having to make a contract. The Chaldea crew would obviously help defeat the Witches, Wraiths, Nightmares, and other enemies. They could possibly reignite Homura's hope that Madoka can be saved, or if this after the Rebellion movie, they would have to save the world from Devil Homura, who isn't that different from other enemies they faced like Kama and Space Ishtar/Ashtart Origin. The Chaldea crew would have to figure out and stop Kyubey and the Incubators.

Another route the story could go (or it can happen in the ending), is Chaldea summons Magical Girls as Servants. For example, Sayaka could be Saber, Mami could be Archer or Gunner, Madoka could be Archer, Caster, or Ruler, Kyoko could be Lancer, and Homura could be Archer, Gunner, or Assassin.