Damaged pipe
#2
You can stick a large screwdriver in the stinger, hold the pipe tight and bend it all back in position. But this small dent should not make a difference in noise.
#4
Cap one end with a piece of tire tubing and a hose clamp. Put your schrader valve on the other. Put in 20 psi, and heat the dent. The air pressure will rise, and will push the dent out.
#5
Really, this is easy to pull out, just a few secconds of work.