I have no idea who these people might be. I do not answer phone calls from numbers with which I am not familiar. This is evidently from an automated system as my phone service disconnects from it less than 30 seconds into the recorded message.
Not the first time I've read about a collections rep with a selective mumbling disorder. The FDCPA requires "Tricia" to give up the name of her employer on request from anyone. Meantime, her managers may have ordered her not to cooperate fully with those requests if an alleged debtor is not confirmed to be speaking. This would be out of fear of nuisance lawsuits for privacy breach, which would lose on the merits but might be settled quietly anyway.
Whether you are called a debtor or some collector thinks you can flush one out, you have rights and options. Many are simple to exercise if you only learn how. You are entitled to proof of claim and fair treatment. If one or the other is not provided, the collection agency should *not* win your assets. You are granted control of how you are contacted, the right to dispute debt claims, and the means to sue violators at low cost. The FTC and the CFPB can start you on your homework. See also if your state laws grant additional or stronger rights.
official FTC guidance and staff opinions on the FDCPA, PDF copy of the Act
http://www.ftc.gov/os/statutes/fdcpajump.shtm
CFPB Q&A on debt collection practices
http://www.consumerfinance.gov/askcfpb/search ... debt-collection