Multiplayer gallery not sharing?

[Soulik]

Hey, i wanna ask.
Today i convinced my friends to buy the game and play it with me.
So i started lobby, they joined, we played a game, got 2 secret endings and i got unlocks in gallery but both my friends did not.

Is this some kind of a bug? Can this be somehow fixed so they also receive the unlocks in their gallery? We played the online multiplayer.

Thanks a lot!