I think is better to combine the list of those birthday boys and gals and the volunteer. If not this is kind of confusing and hard for the other to follow up and put their name there. I would suggest to have it this way
Those who are interested to help :- 1. Eve 2. Lisa 3. Gina 4. Patricia 5. Cin-Di (If Can) 6. Ming Yang
We'll be there to welcome you back at Weld Quay Port, Penang.. Pls try to swim towards the correct direction and not towards Penang bridge ya.. we'll bring along sufficient towels and water for you once you are out from the sea ! AHHAHAHHAH!