That's what she said.
This is what YOU said: "I was in Miami a few weeks ago. Umm, I'd say about 90% of the people I spoke with had a very thick accent. Sure, they spoke English, but they weren't understandable. So, she's not spreading garbage."
She claimed that you wouldn't find "one English speaking clerk", you found them.
They had accents, and you had difficulty understanding them, but then again, I had the very same problem in some parts of Louisiana and Mississippi.