The administrator in Sanctuary who puts Temple on academic probation "for slipping out at night," i.e. for dating on weeknights, is referred to simply as "the Dean" (57) - perhaps the Dean of Women Students.
This man appears in Sanctuary in the story Ruby tells at two different times, to Temple and and then later to Horace, about how when Lee was stationed in the Philippines he "killed another soldier" in a brawl over a local woman (59).
After Popeye is convicted in Sanctuary, this "turnkey" shows considerable solicitude for him, buying cigarettes for him with the money Popeye gives him, but also sharing information about the murdered man and even, on the day of his execution, trying to give Popeye his change (312).
In Sanctuary, as he tells the men at the Old Frenchman place about his troubles with Little Belle's behavior, Horace mentions a young man whom she apparently met on the train coming "home from school" four days before the novel begins (14). She defends her relationship with him by telling Horace that "he goes to Tulane" (14). Though Horace's objectivity on the subject of Little Belle is not to be trusted, this particular unnamed young man seems to be one of several or perhaps many whom she has brought home; Horace sums them up as "Louis or Paul or Whoever" (13).
In Sanctuary the only occupants of the waiting room at the train station when Horace gets there early in the morning are a couple. The man is characterized by the "overalls" he wears and the "rumpled coat" he carries (167). The woman wears a "calico dress," a "dingy shawl and a new hat" and carries both a parcel and "a straw suitcase" (167).
The "official" on the train in Sanctuary who "shakes his fist" at Temple for jumping off at Taylor may be the conductor, or perhaps a chaperone from the college (36).
In Sanctuary there are "two temporary deputies" at the "entrance to the square" just before Lee is lynched, but although the implication is that they have been deputized to help keep order, they are nowhere to be seen when the lynching occurs (293).
One of the two judges at the horse race in The Reivers is named "Ed" (260). We are assuming he is the judge who is first referred to only as "the night telegraph operator at the depot" (229), but it's just as possible that the first name of Mr. McDiarmid, the other judge, is Ed.