Using a VESA mount across a 30" gap
When in doubt, RTFM:
StarTech Low-Profile TV Wall Mount - Tilting Manual
Product dimensions page clearly shows min 300 mm to max 810 mm.
30&quot; = 762mm
300 &lt; 762 &lt; 810
That works. You're good to go!
Oops. As pointed out by OP, that is for the VESA bracket. The wall bracket is actually wider than that, 985mm. You can't go all the way to the edge, but based on the diagram, the usable holes on the wall bracket are clearly wider than the 810mm of the VESA bracket. So that still works out OK.