Earlier quoted context omitted.
They're unambiguously employees - classifying them as independent contractors is illegal, and both the IRS and their state's labor board will take violent exception to it. This isn't the only problem: the post would make a great issue spotter for an employment law class.
I haven't read every comment he's made yet, but skimmed many of them... Why can't they be contractors? He said they're providing their own transportation and supplies. So he's just handing them clients and appointments, and a checklist of cleaning tasks to complete and a few limitations on the supplies used. Isn't that analogous to handing a contracted software developer a requirements document and a deadline?
Would it be OK for the cleaner to subcontract the work?
If so, it could be legit. If not, they're employees. From the original thread, I don't get the impression he'd be OK with subcontracting, so he is probably non-compliant.
That said, I don't think its a huge deal. He'll get audited, he'll pay the owed taxes and penalties and move on with his life. I've been audited by the ESC, its really not that big of a deal.
He's also learned that his customers will pay a premium for good service, so if he has to raise the price, big deal. He'll be fine.