I haven't seen many/any clinics where results were guaranteed (or you were refunded).
Usually you pay for the procedure, not the results.
That said, when I saw your results, I thought they looked good.
It's interesting what the nurse said. Did she mention what a 'split graft' looked like, or what it was? I've never heard the term previously, except where multiple hair follicles were intentionally split to give a more natural result.
Maybe more experienced people on here than me can comment on the second clinics assessment that far fewer than 2000 grafts were transplanted from the post surgery picture to give you peace of mind?
Do you have any pictures following your latest surgery? Perhaps you could post your journey on here?