I would describe it as@- add a 'normal' waypoint
after the 'engage' waypoint, which doesn't need/want to be too far away but so that course is 90deg away from the enemy's course, -at high speed/ low level.
You are on the right lines, but some experimentation may be needed with the exact positioning.
Try watching how AI engages/ disengage from external view(s)
have fun