I just bought Brisky and mine (8 degus) like it, they are not thrilled about it.
I also feed chinchilla pellets from Oxbow and Gerti Guinea pig food (Russell). The added glucose syrup to Gertie and I wrote to the company and was told that there is ony a minimal amount in the yellow banana biscuits which you could pick out to be on the safe side. These brands are pretty good and lots of degu owners feed Gertie, no raisins and such in it.
Please feed them also lots of quality Timothy hay, the the most important part of their diet. Mine like dried tomatoes, dried bell pepper, dried herbs, dried flowers (chamomille, calendula)
I´m worried about molasses as well. It should be better than syrup and sugar though because it needs to be broken down and doesn´t go directly into the blood.
If your degus don´t eat all of their food, you should feed less but make sure that they always have lots of fresh Timothy hay available.