While I agree with your skepticism concerning Priscilla the CIA agent..... I do believe this account of Lee's reaction to the news reports rings of truth.
I believe that he was alert, and wanted to be ready to flee for Cuba, at the first hint that the police were tracking him. Thus he was listening to the radio reports.
Walt, any attempt to crawl inside the mind of Oswald is futile.
People talk about this guy as if they knew him personally and intimately, when they didn't. They base their opinions on what they have been told about him by biased and/or questionable sources. To me, anybody who writes a book about Oswald for the purpose of financial gains is a questionable source unless the quality of the work proves otherwise.
There is so much about the whole JFK murder narrative that is questionable, contradictory or simply not true, that you can not accept any kind of information about the man at face value.
Just take yourself as example... Just how many people around you do really know you so intimately that they can say anything authoritative about your frame of mind at any given time?
Yet, here we all are shaping our opinions about Oswald based on second hand information, guesses and our own bias in considering him either guilty or innocent.