Either way it doesn't sound like there are enough details to know exactly what they mean. A company known for treating workers badly should be more specific.
So some people working in the warehouse are going to be doing it making $14 an hour while others will keep their $30 an hour wage? That seems like a waste of money for Amazon and also terrible for morale.
That is definitely not what the word 'volunteer' means and it is used many times. Nor do I see anywhere in the summary about people being paid. I'm scared to click on the article these days.