I don't think it's an ad, they don't mention a specific brand coconut water.
Goodness gracious me, all the old heads step out for a moment and things that were common advice are back to unknowns. Immature coconuts are nothing more than an immature seed. The water is chock full of the enzymes and hormones a seed needs to develop, same concept as using sprouted barley tea.
The issue is cost mostly; I haven't seen results positive enough to justify anything but buying at costco, which are by far the cheapest. Aloe vera and coconut water both seem to benefit plants needing a kick in the rear more than give healthy plants a further boost.
Would coconut water also be beneficial for germinating old seeds?