No one says the wind is the ENSO cause, simply the SO component, as ENSO was first defined.
Here is a science team that addresses ENSO Chaos via Lyapunov Exponent analysis (no "punting"):
Title: ENSO’s Decadal Dance viewed through a Local Lyapunov Lens
Karamperidou, Cane, Wittenberg, Lall
Columbia NYC, NOAA, Princeton,