@douglasjia RSU that were granted in NY are taxable to NY, even if you live elsewhere when they vest.....that is NY law.
if you look closely at your CA tax return, you get a credit for taxes paid to NY so that you are not taxed twice on the same dollar of income. Review Schedule S on your CA tax return (which I suspect flows to Line 43 or 44 on the CA tax return). If you do not have a credit on these lines, talk to your accountant.
You are required to pay tax to NY on monies earned there. Similar case in CA. You can't just say, hey, I'll just pay it all to CA as it's the same to me. Each state has its own requirements.
On the penalty, you are responsible for the tax return. You signed it, right? Suggest discussing with the accountant (or get a new one!)
