Well done - I will chime in saying that you have proved that not giving up is the way forward!
But I would like to add that Dishpointer is not always right in regards to north/south orientation.
I have experience from settng up a dish in France for 28.2, and Dishpointer was several degrees out!
(I was looking over a mountain ridge, so I had very precise reference points to compare with).
Travel kit for 28.2E in (mid-eastern) France
And one should be careful HOW you use a compass: You need to hold the compass some distance away from the dish when taking a reading.
The compass is of course magnetic (even the iPhone one), and holding a magnetic sensor close to a large metal plate is likely to disturb the reading on the compass. No clever GPS adjustment will compensate for this.
It is very tempting to hold the compass flush with the dish or mount, but this may screw up the compass reading.
I have noticed this on both steel and plastic dishes (with embedded mesh).
My approach is to get the South reading before I put the dish up, and use something on the horizon as reference point.
Afterwards you need to do the check-adjust-check-adjust cycle described elsewhere in thread.