The picture shows the last two fences of the Leipzig race course, however, without the now published design realisation of Course-Collection II. It is the most difficult section of the final curve.

Blue is immediately in front of the fence and therefore is not allowed to change before 8. So the 8 would lead to a fall at the fence #6.

For the same reason the joker 10 would mean a fall. In the minimum Blue needs joker 11 to jump over both fences. But Blue has not got it.

With the 4 blue just jumps over the fence #5, but nothing more. With a high probability this will make the other horses pass and block the inner lanes.

For Blue there is nothing left but to take the bonus cards, hoping to find 6 or 7 and with a bit more luck perhaps joker 11 or 12.