Advice on public transit from Naha to Churaumi Aquarium

Hi, I would love some last minute advice on which public transportation method I should take.

I am leaving from Naha in the morning 9 hours from now and I am limited due to not being able to reserve any busses that require pre booking, which was a rookie mistake on my end for my first real trip.

It seems like the highway bus is my best option (117) from online research but I also see on Google maps YKB888 and the Naha airport limousine bus both leaving at similar times with similar ETAs. I'm unfamiliar with either of these and don't know which payment methods are accepted, or if YKB888 needs to be prebooked.

Which one would be less crowded or more comfortable to sit through the long ride? Would appreciate any advice coming my way!

by itsthanatophobia