@TomD8: I just located Code of the District of Columbia §47–1806.04(a) (at https://code.dccouncil.us/us/dc/council/code/sections/47-1806.04), which appears to be the actual underlying government code determining the out-of-state-taxes-paid credit for Washington DC.
It does not appear to have being domiciled in Washington DC as a prerequisite for taking the tax credit; residency is sufficient. As such, it appears that I can get a credit for New York taxes paid on New York income.
If you would sanity check my reading of that code that would be much appreciated! I realize that you cannot make any promises or guarantees about your interpretation, but I would appreciate it nonetheless.
