Mold or “staining”?

We removed our baseboards and found this after water damage. The mold assessment company hired by building management swabbed unaffected walls and told us there is no mold, and it is “staining” after the water leak. Are we going crazy? This is mold, right?

We removed our baseboards and found this after water damage. The mold assessment company hired by building management swabbed unaffected walls and told us there is no mold, and it is “staining” after the water leak. Are we going crazy? This is mold, right?