Whilst trying some different ways to progress with this achievement we have found an easier and quicker way.
The easiest way we found was to have a group of 4 start match making.
Once the event has started and the race has begun retire from the race straight away.
If any of the group are going for the promotion achievement "Up and Up" -
The Up and up achievement in DiRT 4 worth 207 pointsGet promoted to a new Tier in Pro Tour they need to retire last.
Once you have retired it will count down and launch the second race.
Do the same again, retire in the order you wish to receive points.
With loading times this can be done in roughly 2 minutes for 2 PVP events to register towards the achievements.
I think the person who wins the event will get +2 points, 2nd place will get +1, third 0, fourth -1.
So if one person is going for the Up and Up achievement, let them get it first, then once they have popped it, move onto the next.
I hope you guys find this easier than previous ways.
Note: Make sure you are all in the same handling style. Changing your handling style in the Options > Preferences to Gamer gives your more visibility for match making.