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Yes. Vigorous and persistent use of pruning shears will keep the trumpet vine to a bush-like appearance. This article has a lot of other growing information: https://www.gardeningknowhow.com/ornamental/vines/trumpet-vine/growing-trumpet-vines.htm

This article addresses your problem: https://www.gardeningknowhow.com/ornamental/vines/trumpet-vine/trumpet-vine-no-blooms.htm

When flowering plants don't flower, the cause is usually one of three things. Many plants need to have a certain amount of age, and developed root systems, before they can flower. If you recently repotted yours, they could still be concentrating on their roots. Another is light -- there may be enough light to support leaves but not flowers. A third is too much nitrogen/not enough phosphorous in the soil; you can add extra phosphorous in the form of bone meal, or use high-phosphorous fertilizer.

It's hard to tell, from your description, what kind of worm you're looking at; you could take some to the county extension service, who will be able to tell you what they are. This link will help you locate the nearest one:
https://www.gardeningknowhow.com/garden-how-to/info/what-is-extension-service.htm
Have you tried a Bt product? It works only on caterpillar-type bugs, and doesn't affect other kinds of (possibly valuable) insects. https://www.gardeningknowhow.com/plant-problems/pests/pesticides/using-bacillus-thuringiensis.htm

I would guess that the nitrogen to phosphorus ratio is off. The soil may have an abundance of nitrogen, which would result in nice, healthy green growth but little to no blooms. Without the right amount of phosphorus, it will not bloom well. Bone meal is a great way to add phosphorus.