I was trying to find the same answer a year ago. I contacted Vimeo for a link provided from Vimeo to use to link in the code for the Roku. I have tried multiple times to get an answer from Vimeo and never received an answer. If you get a response with Vimeo please post here. I would like the same answer.
If were easy, everyone would do it. Problems are opportunities to learn, but there is a lot of banging your head against the wall to get there.