They are yes, pointing at the construction map so I guess that the coaster will also have something to do with "terraforming". Could be a really simple reason.
It could be terraforming but the guy is pointing out a straight section of clearance towards the drop. If they want clearance for a coaster they would normally point out an area or a curving line instead of a straight line. A straight section on a coaster / ride normally means hills, a launch or brakes.
The straight section is right after the drop so it's logical that it wouldn't be a launch. Normally you see a straight section of hills only on a big coaster and the clearance is one line (not several spots). It wouldn't be logical to make clearance for the top of each huge hill (I don't think it's possible for them to create several mountains so that the huge hills will be close to the ground). The most logical option would be that the clearance is meant for the brakes.
"The drop" would mean the first drop.
I've never heard anyone say "The drop" instead of "The first drop" for a ride that has multiple drops. If they are saying "The drop" instead of "The first drop" I think that there's a reason for it. Maybe the only reason is because they don't want it to be too obvious that it's a coaster or maybe it's because it will get a droptrack (although it wouldn't be logical to have a straight section of clearance after the droptrack). But I just think the reason for saying "The drop" is that it only would have just one drop.