Given your specific area of pain and the consequent question that just has to leap from the mind to be spoken, the consult with the specialist would need to be based upon what nerve bundle the specialist would plan to address so as to target the flank over your problem kidney? I, for instance, have unrelenting pain from lumbar spine throughout the legs, so my specialist targeted T8-T9, thus producing a nerve result which hits me at the waist and below. The consequent benefit has been fantastic. In your case you just must be curious which nerves the specialist will target to address your specific target relief zone.
Next, a good many of your friends in Ireland have received Medtronic units which either due to its function or placement [ not to say its construction ] have since shown themselves to be of little to no assistance. Also available in your part of the globe is a unit by Nevro which produces no side effect sensation while disrupting the pain, and the St Judes ANS EON if I remember correctly [Jackiey aren't you a St Judes patient? I am beginning to lose track]. Giving consideration to Medtronic alternatives would be worth your while, as each unit has its benefits and detriments. No doubt your country folk on this forum will chime in soon [Sinead? Maybe even Jenna?].
So two major questions for your specialist consultant are addressed above, and I hope above all hopes you receive LOADS of other comments from the folk who prowl these threads looking to add experience, wisdom, and care.
Prayin for ya,
Mark56