Grove Farm plantation on Kauai was running a big 30" system till the early 1960s . I remember travelling through the cane there just after they tore up their railroad ,with rails still embedded in the asphalt at the frequent crossings . An ancient German 0-4-2 and a Baldwin outside frame 0-6-2 are preserved there .
It sounds like the engines mentioned in the article may be 36" gauge .