You may be able to use coconut oil.. The problem is that it's not going to be as water resistant as aquaphor, or as thick since coconut oil will melt on your lips pretty fast. But if you could be diligent and constantly apply coconut oil it may work. There's no way of knowing until you try. I am pretty sure you'd have to apply coconut oil more than you'd apply aquaphor, though.
As for making ec worse, I don't believe there's any way to make it 'worse'. ec is ec afterall, your lips either peel or they don't. I have been using aquaphor religiously for many months and my ec has not got worse, quite the opposite actually.