The gizmo only misses because the gizmo has zero dimension.
The enemy in your picture above has both dimension and appears to be offset downwards.
Therefore your graph connecting that diagonal is not suited to that enemy.
Most navigation mesh making tools allow you to input an agent radius, and then it will create all path graph information while keeping the enemy away from corners.
This is just an engineering tradeoff. Technically by using a smaller radius you are lying to the graph topology saying you can fit past that corner, so it happily gives you a path there.
Another approach is to selectively disable diagonal travel in your navmesh. I’m not sure if you’re making the graph by hand, but if you are, then don’t cut those corners, only allow diagonals when you’re out in more open area.
First though I would fix the vertical offset because that aggravates it on the lower half.
NOTE: many games actually have agents (or at least the visuals for agents) clipping through corners you would think they shouldn’t pass.