Latest update, June 26 2018,
the rebuilt original AUA has been in the car for almost two months, never missed a beat, and it's unbelievably quiet in comparison to my TDI. A note to myself, NEVER listen to mechanics as they want a quick fix/buck and are to "busy" to open and investigate an engine problem. if I had done that myself, 600 euros would have been enough to replace all bearings, pistons, seals and repair the minor damage on the exhaust cam middle bearing.
Instead, it cost me over 1600, but I'm to blame for not doing it myself from the beginning.