RE-4. BC Discharge. Is there any possible way back in or did I royally screw myself out of my dream job?

Technically there is a path
" Applicants with prior military service who were separated or discharged from any
branch of military service for conduct identified as misconduct in the enclosures, require
an enlistment, appointment, or induction waiver from the DMPM. Requests will be
submitted through the appropriate waiver authority identified in Army Regulation
(AR) 135-100, paragraph 1-8; AR 601-100, paragraph 1-13; and AR 601-210,
paragraph 4-7, who will provide a recommendation on approval or disapproval to the
DMPM. " Now that may not be the most current directive, and an attachment I don't have could outline RE4 with BCD and assault conviction are ineligible for a waiver.
But think of it like this.....If the Army needs 1000 new recruits this month nationwide, and they have 5000 applicants..a Former enlisted, with a BCD stemming from an assault conviction who was sentenced to prison for 6 months...... Im as positive as I can be, your application waiver will be round-filed.
Still, there is a path technically, and you fail every time you don't even try. What you are asking is answered by your local recruiter. They have the latest guidance on if you can even apply for a waiver, never mind if a board will approve it.

Go to a foreign country or be a contractor? Find a back door through a State National Guard?

RE4's are double diamond coated armor. The probability is under 5% unless the court overturns your conviction for misconduct on part of the state. If it's a DVA charge: than you have the Lauttenburg hurtle to clear.
IF you clear that hurtle-: its a all uphill battle for a correction of records through the army side.

Not a bet I'd make.

Maybe follow the route that TCAV Official did, go to France and join the Legion. He was in your same boat.

Late to the party, but are you legally allowed to carry a firearm? If not then your chances of serving again are less than zero.

Idk, they a pretty desperate for people.

You might be able to come back in as an overpaid/ underwork contractor.

I think the bigger question is why you did a A/AWD You need to get some serious counseling and explore how you got into that situation. Soldiering and military aside there are so many BIG opportunities in the world out there you need to prepare for that while you are still young and recover.
I had big service aspirations but a physical problem rendered that impossible. I later learned that my disability would not stop me from being a huge success in civilian life - so much so that I wondered why I spend so much time wrapped up about not being able to finish a carrier in the military..
Then again-
If you really want to be a soldier you can always goto Paris and knock on that huge door at the French Foreign Legion...

Look into the French Foreign Legion. No, not being funny.

Well you didn't run to North Korea lol. Screwed is such a strong but true word. Wait until enlistment is down and we are in WWIII,they will probably take you back in. Depending on your job you may have a chance, with a good recruiter and a congressional appeal. I believe in second chances, but with that being said are you mission focused? This may be your dream job, but think about other ways to se rve if the service is more about you and what you want rather than the mission. If you sould be allowed to stay be prepared to start from the bottom do I have the fortitude be treated like a new kid? I wish you the best.

Recruiters make coin on any re-enlistment. And, if you think anyone in California is going to assist you, forget it. The administrative powers in CA are insane, besides the fact that they are "woke" on the military. I wish you nothing but the best; your time would be better spent on job skills that illegals don't have.