Z axis out by 2mm mach3 or fusion360 problem?

[magicniner]

Look at you Z values at the start of the code

G1 x-34.534
g17 g2 x-34.831 y1.008 i0. J0.297
x-18.801 z2.9 i8.015 j0.
X-34.831 z2.8 i-8.015 j0.
X-18.801 z2.7 i8.015 j0.
X-34.831 z2.6 i-8.015 j0.

It starts the cut at Z=2.9, unless you are setting your zero in Mach3 3mm below the surface of your stock then it's going to cut 3mm of air before it reaches the stock.