It's not always easy to visually judge whether a jump should work or not.
One thing to keep in mind when you want the whole party to move somewhere, is that you can select whichever companion has the highest Strength stat, then make them the temporary party leader. They'll have the longest jump range so you can find a place that allows for a jump. Even if the rest of the party couldn't make that jump alone, the game will still let them make the jump to follow the party leader. Feels a bit like cheating, but I use it all the time.
