Very questionable, why would you share such information after just three months? Why risk competition so soon by sharing your business model. Normally people share their business success after a year or two and when they made enough.
What he is doing is simple. Alibaba supplies him items that are in demand like cellphone covers, Chargers, even cellphones and other electronics in bulk. He then ships them to an Amazon warehouse where he stores and until the items are sold(on Amazon as well) and shipped. He is never in posession of the items because Amazon is doing all the work for him. Yes, it can be profitable but it can also be stressful if you're not selling the product and Amazon is billing you for its services.