There are workers in one of the pictures. Clearly, they can access the area with proper safety equipment, e.g. air filtration masks and bunny suits, which mitigates the immediate risk from lead.
One article says that they did not test the regions until May, which sounds more like incompetence than a coverup.
Again, this is no evidence presented that distinguishes coverup from normal bureaucratic incompetence, and evidence is required in order to make as assertion of the former. The latter, I think, is a given (only being a matter of degree in different bureaucracies)