Kraven,
I seriously doubt that your neighbor's pizza dish has obstructed your LOS. That is just far too unlikely and too coincidental here in this case.
Especially since you found your dish azimuth to be off somewhere near 50° from the wind. I am betting that it is still off just a tad or there is
another dish angle that has also been affected that you have not addressed yet. If the wind pushed it 50° out, you had some serious winds
or you didn't have your clamps secure enough.
I have had some stiff winds here on occasion (35-45-55 mph with 70 mph gusts) and I have never had my dish go off more than a degree or two at the most.
Typically, after a hefty windstorm, I have had to do the same as Larobpra did... Just tweaking the longitude entry in my USALS setup to fool it a little bit, but
I was only tweaking it one or two tenths of a degree. That wouldn't have fixed your ordeal here.
You are going to have to find some way to really lock this dish down more securely or relocate it as Anole said, closer to the ground or somehow better sheltered.
RADAR