Hi Apache,
I don't live in the USA but the two doctors in the USA that have seemed to have done well for people are doctor Yue and Regan.
I can understand your son is concerned about going to Germany but there is a link in the FAQs both to Dr Zeegers in Munich and Dr Bertagnoli. Both have done many ADRs Dr Zeegers must now have done 1500 on his own. By 2003 he'd done a thousand!
I can understand the concern about the anterior approach (surgery through the stomach area) but the discs are at the front of the spine not at the back so it's the most practical and sensible approach to take for the surgery.
There's loads of information here, if you look there's Jeff D just posted after 12 months with a three disk implant with Dr Zeegers and he's doing really great.
Best,
Alastair