The El Nino pattern is not an oscillation... it is a fluctuation. Nobody has ever been able to predict the next El Nino based on the historical record. That's typical of fluctuations driven by non-linear phenomena. These are systems that display sensitive depenence to initial condition. Even a trivial research effort should have revealed this. Go read Edward Lorenz 1995 Essence of Chaos.

https://uwapress.uw.edu/book/9780295975146/the-essence-of-ch...

This is really embarrassingly ignorant and incorrect. Classic case of experts in one field having no idea of what's been going on in another field for decades and so making fools of themselves.