If they put down 10 dependents on their W-4 you get nothing because nothing gets withheld. Then the IRS comes after you for back taxes when they see you only have a couple of dependents.
If you didn't file those W-4s on YOUR tax return, the IRS can't come after you. They'd have to investigate the employers who filed the W-4s. Then they'd find out who the W-4s really belonged to. This whole thing is going to cost the IRS millions to straighten out. Maybe we won't have to get rid of the IRS after all. Maybe this illegal immigrant cluster'f' mess will cause the IRS to self-destruct all on its' own.
FICA taxes are withheld no matter how many dependents they list on their W4.
It was overpayment of FICA taxes, not income taxes, that was the point of my scheme.
The scheme wouldn't work because somebody that was already making enough money to exceed the $94K cap on SS taxes would be in a higher income tax bracket than an illegal alien. If the IRS added their income to your own, they would deem you had underpaid your income taxes at the same time as you overpaid your FICA taxes. The refunded FICA tax overpayment would be less than the underpaid income taxes.