Have you given her electrolytes to give her a boost? For electrolytes you can use Rooster Booster, Poultry Recovery 911, Nutri Drench, there a different products available at TSC and feed stores that includes vitamins and amino acids. Or you can make your own electrolyte solution by using one cup of water, add to it one teaspoon of sugar, a small pinch of salt and a small pinch of baking soda. Mix it all up and offer it - syringe if you need to but be careful doing this and only offer one drop at a time on her tongue. In an emergency, we just mixed the sugar and water, skipping the salt and baking soda as we didn't want to take the extra time - we had to act quickly to save a dying chicken. This method worked but the circumstances were different. I am not familiar with Tiagard.
Does she have a sour smell in her mouth? If so, it could be sour crop. The coconut oil should help the impaction, as DobiLover suggested.