Yep, I had the same issue about 2 years ago, left my employer to start my own biz, and wasn't able to access a bunch of Screencast videos I had made under that old acct. Had to recreate them all. Some were AU videos, etc.
Now, granted, I fully understand that some of those videos could be considered proprietary information of my former employer and I'm fine with that. I should have known to grab those needed videos beforehand.
But to be honest, all those I needed I knew well enough to recreate pretty quickly.
Anyway, I have probably a good half-dozen old accts here that I would have loved to combine.
Now, I just use this (my business acct) for most posts and my work acct which I seldom post under.