I play a Jugg so I usually can't get healing medals in war zones. However, if you use an Exceptional Medpac in a war zone, and it heals for over 2.5k, you will get the medal for it. The medpac says it heals for 3000-3675 but for some reason sometimes it will only heal me for like 2.4k, so it won't always heal for over 2.5k like it says it will.
Im not sure if it works with the Heal Consumables too, I have never gotten a medal from using them.