Because he didn’t want to get arkancided, or lose his pension, or have his family members arkancided!
He went along to play along - PERIOD! Durham is as Deep State as Bill Barr, they know when the wheels come off and the American people discover the WHOLE TRUTH, not a single check will be cut for any more Feds! Hell, there will be a price on the head of most people who worked for any alphabet agency - and I’ll bet it is well deserved!!
They are trying to keep a trickle coming into their trough!!