The court may know about uncertainty, but if you look at what Evans said in the witness box, he definitely undermined that.
Here's an extract from the New Yorker article that sparked huge concern about the case, describing one such exchange.
“What’s the evidence?” Myers asked him.
“Baby collapsed, died,” Evans responded.
“A baby may collapse for any number of reasons,” Myers said. “What’s the
evidence that supports your assertion made today that it’s because of air going
down the NGT?”
“The baby collapsed and died.”
“Do you rely upon one image of that?” Myers asked, referring to X-rays.
“This baby collapsed and died.”
“What evidence is there that you can point to?”
Evans replied that he’d ruled out all natural causes, so the only other viable
explanation would be another method of murder, like air injected into one of the
baby’s veins. “A baby collapsing and where resuscitation was unsuccessful—you
know, that’s consistent with my interpretation of what happened,” he said.
If you look at him with the same baby after the trial, speaking to the Guardian, it's the same attitude. He doesn't know for sure what killed her. Yet he's sure it is murder.
Responding to the Guardian’s questions about Baby C, Evans stood by his opinions, and wrote in an email: “Lucy Letby murdered Baby C. Get that into your head.”
https://www.theguardian.com/uk-news/2024/dec/20/my-kind-of-case-intense-focus-falls-on-lucy-letby-trial-expert-witness
It is true that there were other prosecution witnesses. However, Evans advised the police not to take on any other experts, including people outside his field like obstetricians, until he had written his full reports. His reports were then sent to the other experts before they started work, and part of pre trial discussions consisted of him working with them to iron out contradictions. They aren't independent actors.
^^