I don't know the passage in question, nor am I a double bassist, but a great technique my violin teacher used was to play all the notes with a few different rhythmic figures superimposed over the notes.
1) play the passage with the rhythm of dotted 8th/16th pairs. Or even double dotted eighth/32nd pairs.
2) Reverse: use 16/dotted 8th pairs
Try to get these as fast as you can comfortably. These two by themselves are pretty good, they force you to play different note transitions very quickly, while letting you play the alternate ones slowly. Typically 1) is easy, 2) is harder.
You can also come up with other variations with more than two notes, but I have found that even if you just do these two, it brings out the difficulties in different shifts etc, and then playing it "straight" is a lot easier at fast tempos.