FYI. One of the things I do in all my inspections is attempt to determine the discharge point for the dryer. If it vents vertically, I let them know that and advise them to check its function routinely. If I can’t determine the discharge for the dryer, I say that and say it should be traced. I state whether it vents into the crawl and out the wall, directly out the wall, vertically and out a wall, etc. I state the type of material for the duct, if visible, or otherwise state it wasn’t visible.
When I 1st started out, I had a call back about a dryer duct that had come loose in a wall and had caused a mold issue. Of course it wasn’t my fault because it wasn’t visible. But since then, I just try to let the client know how the dryer vents.