In multiplayer, any progression that takes place does not seem to be kept on people who are not the host. So if I donate a mineral to the museum, and get that same mineral the next day, it tells me I need to visit Gunther to learn more about the mineral. If I visit the museum, Gunther says I have nothing to donate. This also happens with the bundles for the junimo. The host completed the first bundle, and when I (as non-host) tried to view the requirements for the bundles, it said nothing was donated for the spring foraging bundle, and would not allow me to flip through to the other, newly unlocked, scrolls. This fixes itself if I visit the community center and see, specifically, that the spring foraging bundle is complete, but this only lasts until the next day. However, the host reports to not have any of these issues, and progression seems to be saved for them. This does not impact quest progression, as I can visit the community center to complete bundles that I can't see from my player menu, but I am not sure if this would be the case if I took this character to a different host.