Selling my home, buyer's agent received "anonymous tip"
I'm in the process of selling my home, roughly 2 weeks from closing on the sale, and the buyer's agent received an "anonymous tip" about an issue my realtor was supposed to have disclosed to the buyer (I assume they did). Long story short, the buyer's agent contacted the county first, and now I have to deal with the county before proceeding with the sale. That however, is not my question.
My question: is it possible for someone (e.g. another realtor) outside the transacting parties (ie buyer, seller & their representatives) to look up the buyer and/or the buyer's agent? If so, how, and what type of database/system (MLS or otherwise) does this person need access to?