if riders are tied for a position in a Speedway GP round, the countback system is used, with the rider registering the most race wins ranked highest.
If they are tied on race wins, seconds, then thirds and fourth places are taken into consideration – with a fourth place deemed better than a retirement or disqualification.
If this does not resolve the tie, the rider who scored the most points in the race or races when the tied riders met is placed highest.
If the riders are still deadlocked, the rider with the highest FIM ranking out of the tied riders is placed highest
Can't be bothered looking back through the scorecard, they must've reached option 4 by the sounds of it.