I’m not a lawyer, but I think her inability to recall a specific date prevented him from defending himself by not allowing him to provide exculpatory evidence (ie travel records etc).
I don’t believe that would be appealable? It would have to be something procedural.
This is not criminal. There is no Brady material (exculpatory). There is only a preponderance of the evidence. Trump presented no evidence as such it is irrelevant she had no date. Her accusations were not countered in a tort. She wins by default.