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,

https://extranet.gfdl.noaa.gov/~atw/yr/2011/karamperidou_WCRP.pdf