Cohen didn't have to spend $250M than he did for Soto, so that's all in Hypothetical Never-Never Land. All he had to do was beat the Yanks, and he knew the Yanks would be just a bit more rational than him.
As for Burnes, I can deal with this hypothetical. It's quite possible that while Cohen thinks Soto is worth every penny, he's not nearly as big on Burnes.