The other relevant issue is whether they are an Amazing Charts partner, which apparently TSI is (listed on the webpage under http://amazingcharts.com/services/partners/ )

Since they asked nicely, they are a partner, suggesting some kind of vetting by AC, I would say let them in.

Wendell
Pediatrician in Chicago

The patient's expectation is that you have all the answers, sometimes they just don't like the answer you have for them