I think you have the perfect middle road between opinions, you have 100k km, if I were you I'll absolutely change transmission fluid just to be safe. (you will hear it is waste of money, and that's true opinion!!)
For my FX35 (7 speed AT) 2009, the manufacturer recommended not changing transmission oil for life (maintenance free) but oil eventually break because it is physics. The question is when?? 500k km?? 1M km? 300k km?? I don't know!!
So you can change it every 100km safely before is too late to change (me on 280k+ I still didn't change and I think is too late to change because what I understand is changing in this mileage will do more harm than good I don't know)
In any case, you must use the appropriate genuine nissan fluid for your transmission. do not ever use aftermarket fluids unless you absolutely know the oil specifications that match the genuine oil.
You also must change at qualified center or by somebody who know what he is doing, because this transmission is completely sealed, not like most traditional tranny.