I created a job posting and assigned it to the "Careers" category.
While viewing the job posting, my theme displayed breadcrumb navigation that included the word "Careers", but clicking on this breadcrumb displayed a category listing without any jobPostings.
My solution was to create a new Post (using just WordPress and Not the RSJP Post) and assign it to the same category ("Careers"). Then I inserted the jobPostings shortcode (e.g. [jobPostings orderby="(post_date)", order="(DESC)", archive="(Hide)"]) and everything works like a champ.