They were promised jobs in Massachusets by Florida, who had no authority to promise those jobs to people. They purposefully didn't notify anyone at DHS in Marthas Vineyard that they were sending migrants there. They were also told they were being flown to Boston and that's where they'd get work. They were instead sent to Martha's Vineyard to embarrass Kamala Harris while she's there. It was all a political stunt.
They're also being housed in Massachusetts (the state Martha's Vineyard is in, btw) not New York. Begs the question where you're getting your news from tbh. California, Illinois and Pennsylvania are all "sanctuary states" as well - so doesn't really make sense why another sanctuary state would be taking in so many migrants seeking sanctuary.
They were also told to change their addresses with USCIS - which isn't the appropriate agency they'd be reporting address changes to. That was a deliberate attempt to get them flagged and fast tracked for deportation after they'd been used as pawns in a political stunt. DeSantis and relevant Florida agencies are now being sued, Texas is being investigated for it's own similar stunt, and the DOJ is investigating both states for being involved in kidnapping and human trafficking.
This isn't even properly about illegal immigration - the Biden administration has stopped more illegal immigrants at US borders than any other president's administration in US history in 2 years. People who live in cities and towns on the US-Mexico border aren't too concerned about illegal immigration either (source: I live in a city by the US-Mexico border) - there's a reason for that too, 1.) legal migration of Mexicans to the US, and vice versa, is easy as fuck - it's mostly the drug war that leads people to dig tunnels and use submarines; 2.) most illegal immigrants to the US enter via airports legally - and stay once their visas have expired.
This was just an attempt to bring immigration to the public eye again before the midterm elections (like that MiGrAnT cArAvAn that suddenly stopped being an issue for right wing media as soon as the last midterm elections were over) and bring a new front to DeSantis's culture war (because his "war on Disney" stopped being popular with his voters once people in Florida, especially Orlando, found their local and state taxes going up as a result... in the middle of the cost of living skyrocketing).
One thing I question: is why the fuck did it cost $500k to hire a jet to fly these people? A quick check indicates a private jet holding 40-50 people is significantly cheaper to hire for one flight that length. So is there some crony capitalism in the midst of this human trafficking scandal? My guess is: yeah, absolutely.
In any case, if the US wants more safety at the border with Mexico - they should be addressing their drug policy and doing what they can to stop their nation's drug problem from making Mexico a cartel ruled wild-west. And if the US wants more protection against illegal immigrants, it's got to be better about enforcement of expired visas.
Trafficking people to states that republicans don't like very much doesn't really solve the issue. Or any issue. It just furthers a culture war that doesn't serve to do anything other than further divide the country. And that's probably being done because otherwise people will pay attention and see that the rampant corporate corruption of America is probably the greatest issue it faces.