I don't see why it shouldn't work, though I've never used the water balls before. But I see that you have a very healthy looking, spiking dendrobium next to it. Where I live, dendrobes and vanda thrive under the same conditions. Vandas are tough and not likely to die in the next 48 hours. Any way that young vanda plant looks extremely healthy to me. Have you considered using bark for the growing medium?