Hello mdoneyes,
thanks for reaching out. Vidsy.tv is a video dedicated CMS that helps our users share more and better video content with their audience, so by doing this you should be able to keep your audience for longer periods of time in your website, which translates into more page views, more shares and therefore better seo.
That said, as you point out as any iframe or js solution we cannot help with the indexation of the widget itself (although there is some discussion on the issue in places likehere and here, we cannot ensure any of this). We do help with meta tags on your user.vidsy.tv URL (you can edit your tags from your “Customize” view, accessible from your Dashboard).
I hope this helps.
Again, thanks for reaching out and please let us know of any other questions you might have.
Best,
r.