Hi I bought a house which had Brazilian cherry floors which were installed with the house 17 years ago. I had them refinished and I noticed some white spots around some of the seams. The refinisher said it was from the previous owner that they used cleaners that caused that. Any thought on this?

Small white spots are naturally part of the grain in BC. You may not have noticed that they were always present because of the finish ambering over time and the natural darkening of the surface.