The literature indicates the order has no effect on efficacy. My speculation is that shrinking the tumor could make surgery easier.
HPV+ tumors are especially sensitive to radiation so I anticipate it will decrease in size dramatically.
Brian and Christine may have more to share on this; I had surgery first as we were trying to find my primary; I only found out via lymph node like so many of us.
Wishing you both the best.
Stef