I'm sorry. I actually reread the article and volleyball is not specifically mentioned. It just says the swimsuits will upgrade after winning "a game", so I had assumed that it would be volleyball.
I'm like 99% sure that, at the very least, Sense will bring back the touch feature and most likely other forms of VR specific interactions.
Since it's hard to picture volleyball working in VR unless they go with a first person mode, which I kind of doubt, I'm thinking maybe instead of that being the focus they will come up with other games specifically for VR.
This will most likely end up being something like Summer Lesson, but DOAX style... Which I am A-OK with.
Also, I hadn't noticed before, but the article says that the 5 Sense games mentioned including DOAX are just the beginning of many big games they have planned, and that all of them will be available for PSVR.