Prosecutors went through Bob Costello’s emails one by one, undercutting his credibility with each painstaking moment—a fate the defense had hoped for Michael Cohen.
Though the defense got a nugget of being able to convincingly call Cohen a thief, they really gave the prosecution the last laugh with their own witness. If the trial was closing right after the prosecution witnesses' cross examination then I would think some on the jury may be impressioned with the idea that Trump could be innocent.
Maybe Lumpy Pillow Lindell would have been an even "better" choice to testify if he was relevant at all to the case.
One is showing that Trump knew he was violating campaign finances, and that he intending to defraud (somebody.)
The other was a thing that was not addressed very well by the prosecution was who was being defrauded. If the purpose of the crime was to defraud voters… he was very late on that score.
(It was in fact government officials and others who read business financial statements being defrauded.)
For the first, I’m not sure you can prove beyond reasonable doubt Trump knows his son’s name, never mind he knows and understands esoteric campaign laws.
There's no such thing as an honest mistake with Trump (well honest anything for that matter).
Nonetheless, you can be found guilty of murder if you hire a hitman to kill someone, even if you didn't know the wording of the statute of how murder is made illegal, and you weren't involved with how the murder proceeded.
So the idea for the prosecution is to prove that Trump asked Cohen to do the dirty work to broker the hush payment, then find some way to cover it up to improve his chances for election.
That's the main link that needs to be shown, and Rob Costello's response that he was involved to help the Trump campaign was a free layup for the prosecution when they might have been on the backfoot at the end of Cohen's cross-examination.
At closing arguments next Tuesday you will get a synopsis of how the prosecution argues Trump is tied into all this.