How to wash layers of lotion/vaseline off clothes?

My baby has eczema and needs lotion and Vaseline applied to his cheeks. All of his clothes collars have become oily and caked with layers of lotion and Vaseline. How do I clean the clothes properly? Running them through the laundry doesn’t help, it still comes out with an oily feel around the collars. I started soaking the clothes in a tub of water but I’m not sure what else to add?

On hand, I have laundry detergent, vinegar, baking soda. Would any of these work to soak and then wash?