Hi, this will not work. First of all the connectors may seem the same, but they are not (pin layout). BeoSound 9000 cannot control a motorised BeoVision stand.
Having said that, I think still it is a nice idea to re-use a BeoVision stand. B&O has made many nice stands. Like for the BeoVision 1. Most of them will go to scrap with the old TVs now.
Will you share a photograph of the result?
Regards, Johan