If someone throws and no one on the card witnesses whether the disc went on the legal or illegal side of a mandatory (due either to not paying attention or because the view is obstructed), is the benefit of the doubt given to the player?

The reason I ask is one hole in particular at Idlewild in Burlington, KY. On 16, there is a mando that's roughly 270' from the tee on the right side of the fairway. When the leaves fill in during the summer, it can't really be seen from the tee. There's been more than one occasion where I thought that I'd cleared it but wasn't really sure. These were all during casual rounds, but I thought I'd ask the question in case it ever comes up. Here's a pic of what the hole looks like from the tee.

yes benefit is given to the player