But the payment happened, there's no disputing that. How or when Cohen confirmed to Trump that he had paid Stormy isn't going to change all that much about the case, if it could then the defense would've called the bodyguard as a witness so he could confirm he never gave the phone to Trump, but they didn't. Instead they've gone with the classic "we think you're lying but we can't be bothered to get to the bottom of it".
This whole prank call business is an oversight from the prosecution but it's not a disaster, especially since Cohen isn't the only witness that has pointed to Trump's knowledge about the payment. Both Stormy and Parker's testimonies were pretty devastating to Trump's plea that he never did or knew anything.
It's bad because it looks like Cohen has used the call to Schiller re the prank calls, and shoehorned in having the phone passed to Trump.
Cohen is a poor witness because he has lied to congress, investigators, on tv shows - you name it. The prosecutors accept this and hope the jury believe that his lies are in the past. But it now looks like he is lying to them - or at very best has misremembered.
If he lies about the call, what else is a lie. This brings in reasonable doubt.
Good point re Schiller. He may still be brought as a defence witness.
We know his is loyal to Trump, but maybe he won't lie under.
The burdon of proof is with the prosecution, so really, it should be them who brings him. But obvisoulsy his side of the story does not fit the narative, or they cant trust him. That brings another issue in because the defence can point out to the jury that the prosecution has selectively not brought in people key to the case - like Schiller or Weisselberg.
Stormy's testimony is largely irrelevant. It damages Trumps character ,but sleeping with her or paying her is not a crime.