The first question, what is the purpose of the earth wire connected to the rails system? Lightning protection or to create a path to ground in case of leakage current.

How do you determine if the installation requires lighting protection or just a leakage fault path?

Then we should be asking, do we need to bond each panel in a daisy chain fashion.

Do grounding lugs/plates mounted between the rail and the panel (stainless steel plate with points) create a suitable low resistance path?

The earth spike, it seems to be another topic where people seem to feel that adding an earth spike is the right thing to do, but is it?