All of the surnames you mention are familiar to me. My area of research is concentrated in the Province of Campobasso. The surnames Cerio, Lembo, and Baranello all appear in the records of the Comune of Campobasso, as well as some surrounding comuni. In present day Italy, the surnames Cerio and Baranello can be found in 43 and 29 comuni respectively, with the heaviest concentration of each in the Province of Campobasso. [The surname Lembo is more diffused throughout Italy, although there is also a sizable concentration in the Province of Campobasso.] While this does not mean your ancestors actually originated in Campobasso, I do think it merits investigation. I have many Cerios, Lembos, and Baranellos in my databases. In particular, I have a Vincenzo Cerio born 10 NOV 1873. If you can give me more information about your ancestors, such as dates of birth or marriage, I will check my films and notes for any connection.
My Cerio line: 3ggm Maria Saveria Cerio (c.1807†1884) was the wife of 3ggf Romualdo Antonio di Soccio (c.1801†1874), the daughter of 4ggf Nicolamaria Cerio (c.1777†1820) and 4ggm Maria Rosa Latessa (c.1787†1848), and the granddaughter of my 5ggf Pompeo Cerio (c.1737†1808) and 5ggm Rosa Pietrunti (c.1731†1812). All of the above lived and died in the Comune of Campobasso (CB).