I need two answers from episode 7.

1)At 17:20, Lisbon and Jane are talking about the Blake Association
Lisbon: "A secret society of dirty cops"
Patrick: "And Red John's a member. Partridge."

Why the hell he came out with Partridge? They haven't mentioned him since he died, and the first thing he can think of after realizing that "Red John is a member" is Brett Partridge. Why?

2)At 19:01, Cho take a photo of Partridge's shoulder. He sends it to Lisbon. Now the interesting thing, look at Patrick's face when he sees the photo, it's like he recognized or noticed something we didn't. Plus, there's a dark sound in the background, as if that scene is very important.(19:08 - 19:11).
What did Patrick see? What does "what do you think it means" actually mean?