Will the video capability of the 9971 handset work is located from a users home connecting back into the cluster via ASA phone proxy.
9971 video using ASA phone proxy is not supported as of now. No roadmap as of now.
There are some cases where customers have done this requirement using Anyconnect VPN. Please check the below link which has details.
https://supportforums.cisco.com/docs/DOC-9124
