'East' in the title explained
The makers of the film knew that Krakatoa was west of Java but they decided to use the word "east" anyway because they believed that would make it more exotic in the minds of the western audience for which it was made. So there is no case of disorientation here, pardon the pun. Try imagining: "Krakatoa, West of Java." But why did they not title the film simply "Krakatoa?" They just wanted to emphasize its orientalness. This was explained by the studio to movie reporters at the time and it appeared in a number of publications including in the Sunday edition of the Manila Times.