More likely, they are probably waiting to get the next variant of the S7 out there in the market (capacitive screen, Froyo, etc.) to boost competitive sales and the population of these devices to justify the startup and manufacturing costs of complex accessories such as the dock which only a fraction of the tab owners will initially buy. The other problem is the "exclusive" distribution of the S7 through Best Buy in the US doesn't help get these devices widely accepted and Best Buy shares some of the blame for not demonstrating any desire to push Huawei to get the accessories out. Shame they (Huawei/BB) appear not motivated to do this because it is the device accessories that ultimately drive the largest profit margins. Hopefully, they'll get their act together soon.
When I first went to BB looking for the S7, I asked two of the sales people where to find it in the store and they didn't even know anything about it. I finally found one on display next to the Galaxy but it was broken. I don't know why they sell them but don't try to push them at all.