Another fine execution brother, it shows you have been seriously working on your Jerry Licks like you said you have, plus listened to everyone here trying to help!! Like I was telling the two younger cats I teach who want to solo faster and more accurately also, practice your scales with your pinky always!! when you play in front of others you can do what you have to make it easier and fend off mistakes, so forget the pinky until it is mastered for live use right now, but it won't take but a few months to master if you start now. As you learn licks as opposed to relearning them later using all 4 fingers you will acquire that skill sooner. You will notice over time the overall fluidity that will help you gain rhythm and speed. You are surely at the point where you need to master that important forgotten finger. Great Job!!! Your broken speaker sounded OK too. Soon enough you will be one of the guys considered to replace a retiring guitarist from DSO who ever that will be in the future.
If you are interested, I have some methods to practice this:
To start practicing pinky moves, find one scale type for right now like a normal C major scale and work it back an forth until you can do it heavy metal fast. Work that into muscle memory, up and down over and over, using an up/down sweep of the pick etc.... I like to work on one at a time, it sinks in easier and faster for me, but it may work for you to do others at the same time. Work some chromatic, pentatonic and arpeggios using your pinky. If you have 2 or 3 scale forms you can practice with the pinky, do it all the time, while watching TV, at warm up, while practicing etc...constantly work on it. We all shy from it because of lack of strength in the finger,so work it out when ever you can. You won't be sorry you did, and your speed and range will double and eventually tripple. That's how all those arpeggio's in Metalica are played at lightning speed, without the pinky you won't be as fast. There is a right hand technique to it too, but your hands will naturally develop the rhythm it needs.
I am not trying to preach, I hope that helps. Always remember you are pulling off music that is not easy to play, the dead's stuff is more difficult than most other 60's 70's rock tunes. You guys sure do have a lot of talent brewing in there. All the best, JB