Is vinegar good for soaking for heel of foot pain?

Not sure it will do : Much. Epsom salt with hot water (dont burn yourself) or ice i think is a better option.

Heel pain: Heel pain is deeper than the superficial remedies can help with. For ice to get deep to where the plantar fascia is hurting at the heel will probably result in frostbite to the superficial skin. See your podiatrist for the help you need.