Is there any reason for a sole member LLC to include reimbursed expenses on a 1099MISC? I'm a freelancer & provided receipts & called out expenses separately in invoices.

I am a freelancer in MA and work with several other small entities (think other freelancers who have established sole member LLCs). In reviewing my 1099MISCs, I noticed that all are only reporting my professional fees, which I expected, except one. One of my 1099MISCs also includes reimbursed expenses. 

I submitted receipts and documentation for these expenses. I also called them out as separate line items in my invoices. When I asked the sole member LLC, the response was that they are still considered a "person," not an "entity" and if they do not report all money paid, then they will be taxed on it - whether or not they have my receipts and documentation.

My question is: is this accurate/correct? 

Thanks!