Yes, you can grow them together, as they are all the same pruning type (type 2 - they bloom on wood produced the previous season, no need to trim except after bloom). I would recommend planting them away from the junipers' roots, keeping them well-watered, but the junipers will be a fine support.

Ditto to what Michael said but plant them well away from the root system of the junipers or they will be competing with its roots for water and nutrients. Be sure to give the plants lots of water and nutrients the first few years or they may suffer since the junipers look like they have been established for quite a long time. You can always use a green landscaping cane or bamboo pole to lead the vines from where they are planted into the junipers.