Dr. Z. carried out a BSSO + chin wing + ZO in one sitting, yes
It was a long surgery (approximately 10 hours!) but everything went well. I stayed in the clinic (Havelklinik) for a week afterwards, just to be sure (I had to travel from The Netherlands). I've been in Berlin for two check-ups afterwards, the next one is in three weeks (Dr. Z. is on holiday now). I'm very satisfied with the ZO, it added a lot of much needed width to my midface, and even some anterior projection.
So far, I can really, really, recommend Dr. Z. He's a very nice and caring person, and seems to be really skilled.