Absolutely NOT! The streaks on your coin have nothing to do with the die. They were on the planchet. It is called an "Improper Alloy Mix." Some call these coins a "Woodie" or a "Woody." Guess it depends where you live.
Yeah, you are correct, but I assumed he was referring to the same thing and just used the wrong terminology.
Since there were no cents minted in Denver in 1921, it was leftover dies from 1920. That completed the order for the 1922-D, since all of the 1922 dies were overused.
I know nothing about the value of coins (I am more of banknote guy), but I did see some of these 1920s us penny on E-bay, but they weren't that much. Unless it was like in new condition and the date goes back way more, like 1910 or earlier.... hmmm