It does if there are hundreds of people watching it continuously.

Planes also pass by overhead. They must be in orbit as well, huh?

Ummm. You need to get a grasp of basic mathematics.

An object far away travels faster than an object close by when both are following the same observable trajectory. It's simple trig.

Even if it were at head height it would still be travelling at many hundreds of miles an hour. This is what we call "fast"

It's got nothing to do with math. It's simple perspective.

We are standing in a wide open desert. There are two cars racing past you at 100 miles an hour from your far left to your right. One car passes you by at 500 feet away and the other car passes you at 10 miles away. Which car appears to move faster, the one closest to you or the one farthest from you?

Aside from the fact that you're denying the fact that hundreds of people observe the ISS continually, I still don't see any reason why you can't apply Rowbothams method of calculating the height. Why do you need two observers? Why do you need two people "standing parallel in a straight line"?

The way to triangulate the position of an object is to look at it from two different far off positions.

If the object is moving through the sky, like say the sun, the observations need to be taken at the same moment in time so that it doesn't change position and screw up your math.

And when constructing the math in the first place we need to know whether the earth is a globe or a plane.

For example, we can calculate the height of the sun by assuming that the earth is flat:

http://www.theflatearthsociety.org/tiki/tiki-index.php?page=Distance+to+the+Sun