How to create a Custom theme for TeamSpeak 6

What’s the right command to start the TS6 client on mac with these args? I’ve tried a number of different variations and they either don’t work, or show some kind of error. This is what I’ve tried:

open -n /Applications/TeamSpeak.app (just as a sanity check)

and

open /Applications/TeamSpeak.app --args --remote-debugging-port=9988 --remote-allow-origins=*

produced this error:
The application cannot be opened for an unexpected reason, error=Error Domain=RBSRequestErrorDomain Code=5 “Launch failed.” UserInfo={NSLocalizedFailureReason=Launch failed., NSUnderlyingError=0x732c186f0 {Error Domain=NSPOSIXErrorDomain Code=162 “Unknown error: 162” UserInfo={NSLocalizedDescription=Launchd job spawn failed}}}

/Applications/TeamSpeak.app --remote-debugging-port=9988 --remote-allow-origins=*

produces this error:
zsh: no matches found: --remote-allow-origins=*