This is a common occurrence and still happens to me once in a while. It will not affect the gummies at all, just keep them in the fridge for long life. What you did wrong was, not cook it long enough after adding the oil to the mix. When I pour it in the mold, I can tell right away if it will happen cause the oil is lighter and you will see it still separated in the pot when pouring into the mold.
Again, it won't make a difference in the gummies- they just won't be as pretty. When done right, you can put the gummies in your pocket and they won't melt. With the oil exposed as it is, at the top of the gummie, you won't be able to do that cause the oil melts easily.
So next time, add a minute more of cooking after adding the oil. You also need to stir the mix really well as you add the oil, as this will help them blend together better. Just keep stirring it until you pour it to the mold. So you know, EVERYONE has the same problem the first time they make them, myself included.
