@TylorValdez1 

"That form will save them over $6000 in state tax."

Only if it applies.

https://www.tax.ny.gov/pdf/advisory_opinions/income/a05_2i.pdf

"The severance payments, including the $7,500 in salary discussed in issue 1, are compensation for personal services that are attributable to past services and if the services were performed wholly within New York State, the entire amount of severance payments is New York source income for taxable year"

https://www.hodgsonruss.com/nonresident-allocation-rules.html

"Other Postemployment Compensation

Other forms of deferred compensation receive special treatment. For instance, under prior law, some forms of termination pay escaped  New York taxation, such as payments under a covenant not to compete contract.  But the tax law was changed in 2009 to make sure that all forms of post-employment compensation could be taxed by New York to the extent the taxpayer worked in New York in prior years."