Hello William,
Look up Spatchcock. Maybe that is better suited to your equipment.
The problem from my view is you trying to follow a chicken recipe vs cooking chicken.
Intentionally reheating a whole roasted chicken is an interesting concept. I would not normally use that technique unless I absolutely had to, due to oven space for LARGE group feeding. (100s of people) Once the Chicken is fully cooked and cooled, reheating will remove moisture. That is what water does when heated, it evaporates. Can't really avoid the science of it...
What makes you think the recipe is amazing? The herbs and/or spices called for in the recipe?
The absolute most important thing about any chicken dish is to not undercook or overcook the chicken. You must first learn how to cook a Chicken. Whole, half, and quartered Chicken cookery each have different cooking times and temperatures.
Rubbing the Chicken with Jamaican Jerk seasoning, or Thai Curry paste, or just some Lemon, Garlic and fresh Herbs will absolutely impact the finished flavor of the dish but, has very little impact on how long to cook the Chicken. Do you think that rubbing 20 cloves of crushed garlic on a whole chicken increases the cooking time by even five minutes? It doesn't... Seasoning is subordinate to the amount of time needed to properly cook "that size" piece of chicken, whatever "that size" is.
If you want to impress the family today, make Coq au Vin or a stewed version of Chicken. Work on learning proper roasting technique and then you can go wild on how to flavor it!
Good luck!