Mineral spirits not drying out of hardwood floor before finishing
I would never put poly down on a surface that was uneven looking as this may magnify the uneven appearance. You may have saturated this area more than other areas, a fan might dry it out but remember the base of your floor is the starting point if it looks wrong now it will look worse with poly in my experiances, you want an even appearance for the entire floor, excess spirits may dilute the poly or cause it not to cure properly it sounds like you have done a good job with the prep work don't rush and you will have a better looking end product.