I've never worked at a Fortune 300 company, so I can't help with that.
However, I did negotiate moving expenses with a charter company. They paid for a moving service to move my household belongings approximately 2000 miles, plus they shipped my car. They also paid airfare for the move as well as two nights' hotel (one night in both cities). I didn't get meals.
There was no written policy at this company either, but the person that hired me wasn't an aviation person - he was management of the parent company. So it was easier to do since he was accustomed to negotiating these items for employees of the parent company. Also, it was his idea.
I'm sure you could do much better as this was just a charter company, but hope it helps anyway.