The rounding rules for Agile, C3, and Brawler say "round each modifier to the nearest 0.5". I've since tweaked that wording, but I'd welcome any wording change you think would make that clearer. The problem is that Brawler isn't a distinct modifier per se unless you work it out by multiplying by 0.25 and then subtracting that; the way Brawler is worded in the text just directly modifies the Subtotal (i.e. it hides the "modifier" part somewhat).
For the Annihilator, you have a PV Subtotal of 40.5. The result after applying Brawler is 30.375. Rounding the modifier's results to the nearest 0.5 gets us 30.5, and rounded a final time to 31.
The Grenadier is the same sort of situation. PV Subtotal of 16.5, multiplied by 0.75 is 12.375, rounded to 12.5, final round to 13.
There's a rounding step here only because everything in the PV formula always rounds itself off to at least a quarter, for overall ease of math.
Also:
I've corrected the HT values on the Grenadier for the base 4-suit squad, but I don't actually know how to modify the 5 and 6-suit entries, so someone else will have to do that (they should be 16 and 18 PV, respectively).