Reminds me of the time the RIAA tried to get some sort of tax or fee out of any sale of a used CD. They thought that the first buyer was paying for his/her use of it, then the person buying it used had to pay them again for their use of it, and so on. I think that idea bit the dust pretty quick. My opinion is if it came to a court trial, you would win, that Bjorn could not stop you from selling the DVD. An argument could be made in court that you were simply transferring the license you had to watch it to another person, and that you would not be able to watch it again. I think that argument would be likely hold up in court. Bjorn would likely fight it tooth and nail, of course, claiming that you did not have the right to transfer your license of it to someone else. If I were on the jury, I would be on your side though. Bjorn already got his money once from the sale of the DVD, he's just trying to get more money out of it.
And when VCRs first became popular 30 years ago, there was a lawsuit by the media companies to prevent home taping of broadcast shows, as a violation of copyright. That went all the way to the U.S. Supreme Court and lost. The court said it was merely "time-shifting" so that people who had to work or for whatever reason couldn't watch the show while it was broadcast, could record it to watch it at a later time. That's not the same issue of course, but I think the law would probably come down on your side, unless you physically signed some sort of contract when you originally bought the DVD, agreeing that it could never be transferred to another person. Ebay is just being chicken by siding with Bjorn instead of you.