In an update from earlier today, Sin Cara did indeed dislocate his finger on the dive onto Alberto during the singles match last night. Dr Samson reset the finger in the ring, and he is getting the X-Ray today to see if any fingers are broken. He isn't expected to miss any real time away from the ring.
Alberto was said to be furious with him because he wouldn't continue the match, thus the attack from Alberto after the match. The promo between himself & Ricardo was just pushed a few minutes earlier.