IMO, this is a high risk / high reward investment. So, all these issues that you keep finding are just par for the course. If you want to look at a 100% safe investment, you might want to try some treasury backed bonds.
Not only broker-trader practices, normal governance will also be under the same scrutiny.
As with exchange-traded securities, investors trading OTC securities are protected from an unethical broker-dealer’s illegal practices by the same SEC/FINRA rules such as Best Execution, Limit Order Protection, Firm Quotes, and Short Position Disclosure