No shoulders is standard on rural roads, and so is a ditch or culvert to collect rainwater. You can see, right opposite TB's place, someone has made a little footbridge to cross the ditch (access to a trail, looks like) so I don't think it is an illusion that the ditch is deep/steep.
Yes, if you break down there is nowhere to pull over and if you do pull over to the ditch you risk flipping your car. You certainly won't be letting anyone out the passenger side door anyway due to the angle (door will hit the dirt).
There's only a couple spots to park within a reasonable walking distance of TB's place.
Yes just a touch south and opposite of TB's place there is a home with a gate that has a flat lawn that goes straight up to the road...so someone could pull up there. But if these people could afford a wrought iron gate perhaps they also laid out for security cameras (there was one security camera sighting near TB's home) and certainly it would peeve them to have someone parking on their lawn (not polite!)
To the north there is a lot under construction with two entrances where one could park. It's a rougher access road than TB's, for sure.
Otherwise the road is shoulderless and bordered by a rather steep ditch.
It just seems to me that they would have first located TB's place, and then had to cruise around to find someplace to park other than TB's place. Parking at TB's neighbour puts them very close and in view of the neighbour. Parking at the lot under construction...well, that's not any better a spot than TB's driveway...if the looks of TB's drive deterred them then so would the site under construction's rough access.
In short it was just a lot of trouble to find somewhere else to park. And that's odd, that they made the effort.
I believe it was said that a third person was involved initially and that they were dropped off!!!!!
If that were the case , problem solved.
If not what if the third person stayed in vehicle at end of driveway waiting for them to come out, so that he/she could follow???? This would mean they would have no need to park up...as not everyone left the vehicle !!!! JMO