I did some further checking of rosters of other railroads in Hawai'i in Best's book. The only thing I found of any certainty was that three Baldwin 2-6-0s from the Olaa Sugar Co. lines on the Big Island were lost at sea enroute to San Francisco in 1950. These were standard gauge engines that the scrappers of the Hawaii Consolidated RR had bought and were shipping to the mainland for scrap.
It might be that one or more of the diesels from Maui and/or Kauai made it to Costa Rica, but Best makes no reference to that in his rosters.
Ed