So then, how did we get 11.3 billion (25-13.7) light-years away from it at that time?
We weren't. The Milky Way Galaxy was still in its formative years, and stars yet to be born and subsequently die and be reborn a few cycles before becoming Sol and its retinue of planets and comets and asteroids. The mass of the MW galaxy was much, much closer to the original Big Bang as was this GNz7q object, and as such was much closer to us. Both we and it are moving away from each other and the BB central location, but not at the speed of light.................