Was there audio in the original video? If not, how could the pilot see that the swimmers were actually in distress and required assistance? It doesn't seem immediately apparent to me that they are in distress. It's pretty obvious they are POTENTIALLY in danger but less obvious to my untrained eye that the danger is real and/or imminent.
Either way, MANY props and pints to all involved. That's a fine example of using technology to improve the efficiency and efficacy of an important job.