I’ve always used hyphens because if I later need to look at or parse the source, it may be difficult to tell what my intentions were. Moreso if for whatever reason I need to code something to handle my files—an unlikely case, but the small effort over time will be instantly realized.
Subsequent to the Panama Papers, there were arrests and financial seizures in many of the named countries: https://en.wikipedia.org/wiki/Panama_Papers?wprov=sfti1#Recovered_money