Before turkey is in the oven, while it's resting on the counter, make the gravy.
Remove garlic heads from the crockpot and squeeze cooked garlic into the crockpot and discard empty garlic heads.
Pour the ingredients through a sieve into a large 4-cup measuring cup. Press on solids with the back of a large spoon to extract all the liquid. If you do not have 1 1/2 cups of liquid, add chicken broth to make up the difference.
In a 12-inch skillet, melt butter.
Whisk in flour and whisk constantly, until the flour gets a light golden color.
Pour in white wine and whisk until the mixture forms a paste.
Slowly add turkey broth, whisking constantly.
Continue to whisk until the mixture comes to a boil and has thickened. At this point, if gravy isn't as thick as you like, continue to boil, until enough liquid has evaporated to create your desired consistency. Adjust seasoning, to taste, with salt, pepper, and Cajun seasoning.
Pour into a gravy boat and serve with turkey as soon as it comes out of the oven.