When couple did some research, they found out that the broker was actually liar and was very irresponsible. Previous owners did inform him about the room and and mold issue. But he chose to turn a blind eye towards the issue and was completely ignorant of the fact that this might actually become fatal for someone living in the house. The previous owners did their part by informing the broker and also leaving a note behind. They made sure that no one has to suffer the way they did. They definitely were good people.
Later the couple sued the real estate agent and the home loan corporation. They deserved it. But they must thank the former owners. It could have been a disaster if they would never find the note.