As others have noted, getting good legal advice from a qualified attorney in Texas is your only option if you want to pursue this further.
Can you afford to spend no more than $20 for a 30-minute initial consultation with an attorney? If so, you should call the State Bar of Texas
Lawyer Referral Information Service and ask for a referral.
It sounds like you may have grounds for a civil suit but you'll definitely need a lawyer in Texas to help you figure out if you have a viable case and claims that aren't barred by civil statutes of limitations.
Regarding the misdemeanor assault case, there are a few things you should understand:
1. In Texas, a municipal court judge does not have any authority to order an investigation into anything.
2. In Texas, the maximum punishment for a Class C misdemeanor is a $500 fine. Conviction of a Class C misdemeanor does not impose any legal disability or disadvantage.
3. The attorney representing the state (in a Texas municipal court, it would likely be a city attorney) prosecutes the case. It their job, not yours, to persuade the judge.
4. In Texas, indictments are only used for felony cases.