You have to keep in mind that you're not listening to a journalistic expose of the Trinidad election -- you are listening to a sales pitch from Cambridge Analytica, which has all the motivation to vastly exaggerate their influence. I've been unable to find any reference to this "Do So" campaign anywhere except for Cambridge Analytica bragging about it. Furthermore as described this was an old-fashioned campaign, which had more to do with physical materials handed out than social media ads.

The same caveats went for all the "psychological targeting" they bragged about a few years ago; there is precious little evidence that it is better than targeting roughly by political party, which we've had for decades. For its power, we only have their word to go on.