Tax I agree with the part of being foreign sourced etc.
If they are withholding, then they best be paying it to the US Treasury, so you can claim the money back on by April 15th.
Death and Taxes, you can not avoid them!
Just ask RD what the tax ID number is and where the money is going, he should have a clear explanation of the entire situation as he has had 2.5 years to figure it out.