Sorry to hear about your experience with HCG. They are one of my all-time favorite mail order nurseries and I love their selection of unusual plants. That said, I don't think I have ever found any nursery that gets it 100% correct all the time. It is just the nature of the business. What sets a good nursery apart from a mediocre one, however, is how customer service handles complaints.
A couple of things to consider:
1. Did you tip the plant out of the pot to get a look at the root system? This could give you a better idea of the age.
2. Are there any trimmed off stems at the very base of the plant? Caryopteris is sometimes grown as a die-back perennial, and the plant could just be trimmed back and semi-dormant right now.
Of course, the other option is that the plant was indeed too immature for shipping. If that is the case, then shame on HCG! However, not every staff member of a large nursery--especially those at the bottom of the ladder who are likely doing the pulling and packing-- will know enough or care enough about plants to know how to select good specimens. Good plant people are unfortunately in the minority. Bad plant material is not always shipped intentionally.
HCG does have a 100% guarantee of their plant material for 1 year. Please call customer service and ask them to remedy the situation! I think they also have a claims form on their web homepage at the bottom right of the screen.
I love HCG and have been ordering from them off and on for years. I have received a handful (maybe 3 or 4 at most) duds from them over the years, but I have never had a problem with replacements.
I do hope your new plants grow well for you. They will be beautiful additions to your garden!