I agree with you, HOWEVER, we have yet to see or hear rumors of any type of search warrant(s) being executed in the Bahamas or the US.
As we saw with the Fyre Festival guy and other similar fraud cases, the government wants to move quickly to secure physical hard drives. In the case of that dude, Fyre happened on Thursday and they executed a search warrant at his apartment on Monday morning.
It’s possible that grand jury subpoenas have already been issued and served, but that doesn’t typically generate the criminal intent evidence they will need for this case.
We also know from former employees that routine business was typically discussed on Signal. That’s probably not a great sign for the government as they will need physical access to the devices used OR they will need to snag an iCloud (or other) device backup and grab the contents from there.
Your points about a speedy trial and losing a case are generally valid BUT the DOJ can always opt to file a superseding indictment once he is in custody. I don’t know the full deal with Extradition from the Bahamas but it’s likely it will take some time (several months). Despite this being a white collar case the government will absolutely seek to keep him incarcerated given his flight risk and resources unaccounted for. Anything he’s embezzled from FTX in the span shortly before bankruptcy will be used by the DOJ as proof he has hidden resources.
Remember, in pretrial arguments, they can come up with pretty far fetched or ridiculous arguments that have no merit or bearing later on. For example, in the case of Marcus Hutchins (the WannaCry kid), prosecutors argued he was potentially violent because he visited a shooting range several days prior. He was, in fact, in Las Vegas for DEFCON and went to one of many shooting ranges advertised on the Strip.