Does anyone doubt we have the capability to find and track these Chinese agents, especially they way they are so blatant about it in the Chinese community?
So, the FBI picks them up, and has them on a plane to Beijing that afternoon.
The essence of good counter-intelligence is usually not disclosure but to watch and then neutralize or recruit the agent so as to double them against their handlers. Unfortunately, the Chinese rely on a multiplicity of agents, many of whom are amateurs, so there is a tendency for some to slip past our detection and screening effort.