I had this problem as well two nights ago when in queue with two other friends. Two of us got the black screen and dodge penalty while the third friend got into Champion Select.
This is very frustrating, just got into my promotion series, go to que up, and soon as i accepted the invite got this exact same black screen and wasn't able to see anything.
Short while after "retrieving information" box came up with a cancel button, after which it just took me back to the game client, checked my history and I had lost game 1 of my promo series. Very Frustrating please respond with at least acknowledgement that your aware of this Riot!