Floor purity

a relative has laminate style flooring in their kitchen. They needed to mop it as there was lots of dust due to renovation in the kitchen. They used a mop to do this but the mop used was an old one that is currently used in the toilet/bathroom. The relative did wash the old mop in the sink with cleaning liquid then used the mop to mop the kitchen floor. My question is has this made the kitchen floor impure due to the fact that the mop was previously used in the bathroom which can be impure due to traces of urine/najasah. Although it was washed in the sink, it may not have been washed enough to remove the impurity. (I’m concerned due to the fact that wudhu is done in the kitchen sink and wet feet then put on the floor). Jazak’allah