Losing WCBS as an outlet for CBS News on the hour will not be fatal for the network. It still airs news on the hour on KNX Los Angeles, WBBM Chicago, KCBS San Francisco, etc. ABC and Fox also have no NYC affiliate. And even if it isn't taking the news on the hour, WINS uses CBS actualities and field reporters' stories in its regular news wheel.
CBS Radio acquired WINS and KYW Philadelphia from Westinghouse when it merged with CBS. Through their all-news history, WINS and KYW didn't air a top of the hour network newscast, while all the CBS AM stations carried CBS News. This continued, even after WINS and KYW were merged into CBS Radio.
So to this day, WINS doesn't carry hourly CBS news and KYW only does it a few hours overnight, when some of its regular news is prerecorded. Same story at WBZ Boston, which was also a Westinghouse station. It only airs CBS news on the hour overnight when it runs prerecorded news.