I would also suggest assessing the superio tib fib joint in about 70 degrees flexion. Mobilisation of the joint might well reporduct some on the symptom or might reduce the symptoms after mobilisation.

If is is implicated then you either have an issue with rapid pronation during stance and or excessive hamstring influence across the keen during loading. Gluteal work etc for proximal stability will be part of the way forward. In any case a calf issue following a run is likely to be due to over work in some way, more likely due to the cumulative effects of prior training rather than the run itself. Treat is like something more of a chronic nature and enjoy looking at and fixing the fundemental biomechanis of his running.

If you are setting up a sports clinic get out the video camera and watch him run. This will give you the most information. Look at the soles of the feet, first ray, great toe etc to see the repeated effect of loading. You might well be able to diagnose the problem without even touching the calf.

As for the back, well it is going to be tight somewhere, in some direction, it always is! Well almost always. Addressing it is important but if you look there you will always find something to address, just don't base you diagnosis on it (to many false positives).

Can you give a bit more specific info about exactly where the pain is. Pain on EOR flexion should also be able to be palpated with the patient in prone and the knne gently flexed to relax the gastrocnemius. Have a "dig" in the back of the knee with the muscles in a relaxed postion and tell us more precisely what you find