Hi, I had an entrepreneur ask me this same question recently. Based on the information Apple Provides you can definitely enroll with a DUNS number. There is a difference in the process of enrollment but both sole Proprietors and Organizations can enter. Here's a quote directly from Apples on business procedure.
"Sole proprietors/single person businesses can review the license agreement and purchase a membership at the time of enrollment. Organizations can review the license agreement and purchase a membership once Apple Developer Support verifies the enrollment information and sends an email with next steps. You can check the status of your enrollment in your account on the developer website. Be sure to sign in with the Apple ID you used to enroll."
Hope this helps. Feel free to request a call with me, I wouldn't mind helping you analyze the situation so we can streamline you on your way to the answers you need.