What is the possibility of an 88M getting stationed in Washington DC?

There are a few nominative assignments that you must compete and be selected for. You will need CSM mentorship at a minimum. See what is one ASK and call your branch manager. There is more than just the Pentagon. You have Ft Belvior, the Department of the Army's HHC and Garrison. Ft AP Hill. Be careful what you ask for, you might get it. I knew an 88M who was the SMA's driver.

Who in the hell would want to be stationed in that shit hole. I was once

Look at the White House Transportation office.

Ik they have the 3rd infantry regiment there or "the old guard" as a heavy vehicle operator. I to am interested on that position.

Outside of the White House transportation Agency there are not a lot of slots in DC or the surrounding places like Belvoir. You have a better chance of getting a slot in Belgium