Looks like it's game over for me.
My save's definitely corrupted. Arcadia island doesn't show up in map, and even though I finished the game, I can't progress Astral Archive cause the bard is bugged and doesn't count my win. Weirdly enough, the darkrealm fast travel exist. Also in Chapter four of Ghost of Hope, I can't progress Tsugio's death cause I can't place the golden snake on the pedestol. It shows up for a quick second and doesn't do anything. Using the snake also doesn't work, so yeah, my game is completely broken unless I start a new game altogether, or completely ignore the Ghost of Hope Mythos.
Rip. It was fun, I guess.