Marina said lots of things that were either inaccurate or outright wrong. She also had a very poor memory it appears.
And lastly, she wouldn’t have been able to testify against her husband had he lived to stand trial.
This is a common CTer trope. Marina certainly couldn't remember minor details of events or exact dates months after the fact. Almost no one could. It was only in retrospect that such details became important. She also had an incentive to be vague about evidence incriminating Oswald. She was subject to criticism that maybe she should have been a little more concerned with his activities and bears some responsibility for what happened by not reporting him. To the extent that we know of any efforts by Marina to cover up evidence, it was to protect Oswald not incriminate him. It borders on the incredible that CTers cite such incidents to suggest she was lying to incriminate Oswald.
In terms of the Walker attempt, when her husband came home late at night and told her that he has just tried to assassinate someone, that is something to be remembered. Just because Marina couldn't remember specific dates of minor events doesn't mean she had a poor memory or couldn't remember being told that Oswald tried to murder Walker. The fact remains that Oswald confessed this crime to his own wife. He did so before the public was aware of any such crime. There were recon photos of the Walker house found in his possession to corroborate this story. He left a note telling Marina what to do in the event of his arrest or death that night. What was so dangerous that Oswald anticipated being killed or arrested for on that night? His typing class? This one is a slam dunk.
