I have photographed a wedding where the cake was served poolside after dinner. And also one where they cut the cake in Don Pablo but then had it at the poolside reception with plates and forks.
I will say, it's a three milks cake... and it's really hot outside... so I'm not necessarily sure it should sit outside for that long, but it still tasted good and I didn't get sick! Ha!
Their desserts and their cakes are so good! And the poolside reception is right by the buffet. So honestly, if someone wants a different dessert than what you choose, they can go right in the buffet and grab from a selection of about 20 different dessert items! So do what you want. If you like the look of a larger cake, then go with that and don't worry about the little desserts