Interesting that they are proposing to use the wood to fuel the sugar extraction process; given that the bagasse left behind from the crushed crop is an energy dense material, most sugar plants use just that for energy supply and even have spare electricity to export. Suggests (as indeed the quoted article states) that Cuban sugar plants are pretty primitive.
Using the notoriously unreliable Wikipedia suggests that marabu is Dichrostachys cinerea, another legume like the acacias. So no wonder it grows well. The pictures of it on the web show a timber of very similar colour to acacia/false acacia/laburnum, with dark brown heartwood and yellowy-white sapwood.