World News Roundup: 09/27

<p>Investigators search for the cause of a deadly weekend Amtrak derailment.&nbsp;Concern about staffing shortages as New York's vaccine mandate for healthcare workers takes effect.&nbsp;Liz Cheney says she was wrong to oppose gay marriage.&nbsp;CBS News Correspondent Steve Kathan has today's World News Roundup.</p><p>See Privacy Policy at <a href="https://art19.com/privacy" rel="noopener noreferrer" target="_blank">https://art19.com/privacy</a> and California Privacy Notice at <a href="https://art19.com/privacy#do-not-sell-my-info" rel="noopener noreferrer" target="_blank">https://art19.com/privacy#do-not-sell-my-info</a>.</p>