If Juvederm is placed incorrectly, it will normally shows up as bumps or slightly bluish skin discoloration. If the bumps are less than 1mm and white, they are likely sebaceous glands. These are normally present on the vermillion (pink part of the lip) border especially on the upper lip. Usually they are 1mm or less in size and white to yellow in color.
Sebaceous glands make the oil for our skin and occasionally get blocked. It is unlikely that these blocked glands were caused by the Juvederm. They can be removed with aggressive microderm, TCA acid peals or very minor surgery.