Wow, is he tiny! Sounds like you are doing all you can do. He will probably bond with you to the point that he thinks you are a quail or that he is a human!
I once had a clutch of Lovebird eggs that only one bird hatched. Lovebirds desperately need companionship and a mate, to the point of dying if their mate dies or they are without a mate all their lives. Hence the name Lovebirds. Well, this little lovebird did live. She became so attached to me that I became her mate. She did everything with me, hanging out on my shoulder ALL day long. She hated going into the cage at night or during the day if I needed to leave, and would throw fits of rage when I left her. But she lived a long life, well past her expectancy and had a wonderful life!
So I imagine that this little guy will make it if you give it enough attention. Good luck with the little guy!