The silencer and possibly the subsonic ammo caused it to jam so he had to keep racking it to fire. He left three casings from the shots and three live rounds on the ground from the jamming.
The suppressor was 100% a wish or temu "flashlight" kit, not legal. Legal ones are usually sold with a neilson device for use with tilting barrel pistols (like glocks), since his didn't have one the combo was too heavy to cycle the slide. He also had trouble going back into battery a few times leading me to believe it was a poorly milled "ghost gun."