Couldn't you install the new vshare. Then remove the new database (backup first). Put in your old database. Run the upgrade.php. Then go in with myphpadmin again and delete all the video records. There would be other things to delete too though, such as comments, favorites, ratings, friends, etc. But basically you now have all your users.

One thing to keep in mind when upgrading to 2.8.1 that I did now know about and I don't know when it changed as i was upgrading from 2.4... The paid access is based on number of videos viewed. In 2.4 and maybe others it was based on MB viewed. So I upgraded in the middle of active accounts and the new db does not even keep track of the amount of data that is viewed only that a user has clicked on a video. Not a big deal once I noticed it and changed any advertising information.