Glad to hear your shifting issue is resolved! That's good news.
However... if the fluid & filter has never been changed (or, you have no record of it).... I'd highly recommend that with 100kmi on the clock. These transmissions are not "filled for life". The "special" ATF is not that special, it's 236.14 spec, and Red Line D6 works just fine. Newer models that require the blue 236.15 fluid are a different story.