Are you talking at cross purposes here?
From the private balcony of 606, one cannot see the entrance to the Tapas zone, let alone the front or rear of 5A.
Mr Mackenzie does not say private balcony, he says public balcony, which is the access balcony at the front of block 6 (the car park end).
Now that balcony I have been up, twice from memory, because it is public, not private.
I did a revisit because we were debating whether or not one could see the front and rear of block 5 from there. I was able to see both. I cannot remember with certainty if I could see the front door of 5A, but from memory, I think I could.
This proved a limited amount because all of the time I have been interested in the case, the trees at the east end of block 5 car park had been removed. So I do not have a view through the trees. If one exists, Heri and the newspapers are potential sources.
I don't remember being able to see the Tapas Restaurant, short of doing a Tarzan over the balcony ledge.
The block is numbered 601 at the east end ground floor to 605 at the west end. Then it is 606 on the 1st floor east end to 609 (from memory) at the west end. I did check how it was numbered above at the west end, and from memory it was 613.
I can re-check all of this if it is critical, but I can't see how it is, given I cannot put the trees back in place.
Presumably Mr Mackenzie noticed the butts because he was close to them, but I have no certainty as to which apartment he was relocated to.
A year after the disappearance, Neil Berry thought he might have been in apartment 4G. He was actually booked into 606. Luckily his statement has enough information to confirm he was in block 6, 1 floor up.