Chapter five: The second Jeep is neither seen before nor after this chapter.
Chapter four foreword states that Jean was tied to a tree by Cass and Rand so that some jungle beast will kill her. Actually it was two Returi natives that done the dirty deed.
In the lead in to this chapter play Phyllis Coates mentions Mato Grosso (which is a state in Brazil.) Since this picture takes place in "Africa" this is definitely an error in geography.