If they live in AR and can naturalize if they don’t have Argentine citizenship already that might be the better option. Southern Cone is much lower fraud risk than northern LATAM so given all that’s currently going on, I’d personally prefer to apply from a lower fraud area. Northern LATAM isn’t Nigeria, but it’s still higher risk than Argentina/Brazil/Chile/Uruguay.
Said another way: Trump isn’t likely to have issues with Milei anytime soon but there’s tensions with Colombia over the situation in the Caribbean, so having another option doesn’t hurt.
The passport won’t really be needed for 11-14 months when they file the DS-260, so they have a year to do it.
Colombia would also very likely work, just throwing out potential options and considerations.