Turbo damage… or not?

Hey on my part, My Italo has taken the worst place. In my underground garage. The boat just doesn’t start anymore, sounds tormented and the exhaust gases press out of the open oil cover during the start attempt. So the car won’t get rid of its exhaust gases. I wanted to unscrew the downpipe to see if the cat may have disintegrated but I can’t get the tube off the turbo. Heat plate is gone and the 3 screws on the downpipe to the turbo. Did I miss anything? Inter It is essential that when I manually press the shaft at the Wastegate the car starts. It only runs with 500 revolutions and like a sack of nuts but it runs. That speaks more for the turbo….as if the shaft was tight. The next step would be to decompose the intake hose to see if the shaft can be rotated from the turbo on the suction side. Does anyone else have an idea of what I can check? As I said, the car is stuck in the underground garage. (A pull-off from the charging pressure hose does not bring any change. Fresh air it seems to get but only its exhaust gases will not get rid of.)