Domestic flight -Danang to Nha Trang

Hi,
My friends and I need to get from Danang to Nha Trang on April 4th, however only one flight per day which the online agent tells me is fully booked (for 3 days running).

What are my chances of waitlisting and getting 4 tickets?
If we cant fly, would you recommend train or open-tour bus?
We have booked a resort at Nha Trang (and paid) so have to get there on April 4th!

Any assistance would be great!

Only bus I know of is an overnight one and from experience I would not suggest to take it. Soft sleeper in a 6 berth cabin overnight train was around $15 and took around 13 hours. As an aside, the plane does not land in Nha Trang but instead lands in Cam Ranh which is around a 45 minute drive away. I would still try and book the flight when you first get into Vietnam.

Rent a mini van. Not sure on the cost but maybe around 175usd? Will be faster than the train.

We found it difficult to get train tickets from Danang to Bha Trang. In the end, we opted for "soft seat" non aircon at 137,000 dong, water and meals included. Left at 0610, arrived at 1800.

The train is the best way to go. It's comfortable in the soft seats and quiet, plus they will feed you for free. I've taken the bus, car, van and plane all over Vietnam. The train is the best for comfort but the plane of course is the fastest.
curt