yO, I have never seen a Cuban Beetle, But here on Central West coast Florida I have used Triple action Neem oil and has worked very good for me, I had an infestation of spotted mite last year, and NeemPlus , was the only thing that worked for me, with those mites. I have used a Orthene 97,it is for trees and Plants. Here some nursery's use it on all of their plants. I used it on white flies ,this week,and seems to be working. It is a take no prisoners, product, will kill lizards and all slugs, snails ect.
Caribbean Carlos