(((hugs))) Picky toddlers are so stressful. Firstly, your aunt is right: he will not starve himself. It is something that he cannot do, as long as there is no physical reason for him not eating. I have to say, though, I'm not sure that I agree about time out - the best approach when they are being picky for the sake of it is to not let it become an issue. So ask/make him sit with you when you sit down to eat, and then if he doesn't want to, let him get down from the table - really light and airy "oh, you're not hungry. You can get down from the table." But you have to make sure that he cannot then come back when it suits him to eat whatever he likes - one way to make sure that he doesn't get too hungry is to have scheduled snacks in the day (when I was going through this, I found snacks were a good thing because they meant that dd didn't have the blood sugar dips which often led to her being cranky and us having a battle). It also makes it easier for you to let him get down from the table because you know that he will have something in an hour or so and he won't make a fuss because he is hungry! Having said that, my dd often went to bed without supper because she refused to eat it, and we never had problems with her being hungry.
I also suspect that you will have an easier time of it if you try to have meals at pretty much the same time every day - that way you can plan activities to make sure that he is not having to stop doing something to come to the table.