Did that actually have the old stain completely sanded off? Because it doesn't look like it did. And then applying a stain on top of a finish, it won't dry. Then a finish on top of a wet stain? You get trapped moisture and blush.

these are refinished? by whom and by what?

can I see a before pic?

sorry, but I agree w/above. these don't look properly done.

the gray you're seeing is the poly that hasn't dried properly. have no idea how they applied it.

give us a pic showing all of the floor. when you say the rest looks better, how much better?

Are the floors completely dry? If so, these are chemical reactions to the pet stain. The stain needs more time to dry before the water base poly can be applied. Redo the boards affected.

the rest of floor looks fine. i got them to agree to apply a semi gloss polyurethane as the two coats of satin are very dull. Then I saw the streaks. I will show a before (sanded )

and another after

THANK YOU everyone for your replies. Waiting to hear from company.