Absolutely ask for verification of transcripts. I have this done via my nurse. Hardly any agencies do it though, do not be surprised if they put you off, or simply stop returning your emails and calls.
Video - what an interesting question!
I have to tell you, I easily found a donor early on in the process, and yes, I found video online...which is why I decided to not proceed with her. It told me a lot...not just about her integrity, but also her personality. I think that is an interesting question.