Would someone be able to explain how brake dive differs from yaw?

"yaw" would tend to spin the car along an axis perpendicular to its roof (i.e, viewed from the top, the car spins clockwise or counter-clockwise). This happens for example, when you are braking on a split-coefficient surface: dry asphalt on the left wheels and gravel on the right. The braking forces would tend to rotate the car counter-clockwise when viewed from the top, with the front of the car at the 12-o-clock position. It can also happen on acceleration, for example, with only the driver on board, and the right rear tire lightly loaded. ESP & traction control systems with yaw control apply different braking pressures on each wheel to counteract this imbalance.

rotation along an axis perpendicular to the side of the car is called "pitch". This can be caused by deceleration forces (brake dive on front & rear lift) or acceleration forces (rear squat and front lift). These forces are counteracted typically (passively) with suspension geometry; more advanced cars with active suspension deal with them actively.

pitch can also be caused by undulating road surfaces, e.g., expansion joints on the highway. A long-wheelbase car will have less pitching than a short-wheelbase car. Active suspensions can also reduce their effects.

if the axis of rotation is longitudinally along the car (i.e., perpendicular to the front of the car), it is called "roll". These are controlled passively via anti-roll bars, or actively via active suspensions.