This is pretty standard for deals like this, Nevada gave Tesla 1.3 billion for the Gigafactory. This "could" draw 3 billion. It's just tax incentives, not like it's a cash payment. But anything to make Trump look bad I guess.
What happens is that the jobs up and move as soon as the subsidy ends.
There has been quite a bit of research done on these kinds of tax subsidies and they almost always cost more than doing nothing and not getting the jobs.
Its a fictional difference that is used to make it seem more palatable.
Governments don't have a great track record of picking winners, and companies that are capable of stealing headlines don't necessarily have a bigger or better impact than thousands of unknown businesses.