Prefinished hardwood floor uneven between head and butt
My answer would be, especially since he offered, have the contractor do just that - resand the whole thing. You don't pay for a prefinished hardwood floor expecting to have little bumps and divots in it. Our house has original hardwood floors, that we had refinished a few years ago. After refinishing, they were as smooth as glass, all the way across the room. If you just leave it now, most likely those little uneven spots will nag at you and bother you more and more until a year from now you will have to pay someone to resand the whole floor. Just my 2 cents worth. Hope this helps.