Interesting discussion. To answer the original thread title, yes I offer foundation measuring. I’m not familiar with this particular method of documenting the findings, but I believe it can be useful even if it requires explanation. In fact, I like the idea of the client needing to contact YOU to come back years later and take new readings for comparison. $$ 
You have created a “baseline” reading for them, even if not from when the slab was poured, they now have one from today and can compare later if needed.
I use and generally see a simple drawing of the floor plan with the elevation readings plotted out. The reference point is usually in the center of the house, but I may change it later based upon the readings. Many engineers and foundation repair people make the highest point the reference to show the total deflection/slope from that spot in the house.
I’ve taken Joseph’s model and chart and made a crude drawing by plotting out the readings making the high point of + 2.1 inches the reference (REF 0) and showing the other measurements in relation to that spot. I don’t know the orientation of where those readings were actually taken, so my drawing just assumes it a simple rectangle and the bottom is the front of the house. So from this we can see that there is an acute high spot (could be a heave, could be some other anomaly) and the slab is at least low at the front, right corner.
I’d need to know more about where damage was visible, how the garage readings were taken, etc. to say much else. As a home inspector to my client, I am probably going to say even less.
Any other opinions?