I seriously doubt what you saw was actually the dust clouds the Pleiades are passing through, but scattered light instead. The nebulosity is only visible from dark sites while the sky is clear and the moon absent. You could have seen the individual concentrations of interstellar dust with your telescope under those conditions. The drawing below was made at the 2016 Okie-Tex Starparty under very dark skies.
Achernar's sketch is fantastic. The Merope nebula should be the one you are targeting given that it is the easiest and you are working with less than ideal conditions. The first time I saw it was when I focused on the "extension" of the nebula out and away from Merope and towards the ~magnitude 8 star in Archenar's sketch
Binoculars usually provide a better context for seeing these type of nebula- more sky with which you can compare the "edge" of what you think might be the nebula. You will also need a fairly dark sky the first time you go for it.
That being said, once you catch the Merope nebula, it can be seen in more challenging conditions.