They wiretapped Carter Page. Page and others in a meeting with Trump nixed Papadopolous’s suggestions of meeting with Putin, other Russians...
So did Manafort.
I think Papadapolous tried everyone he could after that, and may have been the one who suckered Trump Jr.
Papadopolous was either working for the FBI then or for Chris Steele who was working for both the FBI and the Hillary Campaign.
A poster here thinks they are going after Jr