Yes, the only time you can get into the back room is when he is listening to the bard.
Unfortunately I blew half my window here. By the time I realized he wasn't coming right back, I'd spent half the time standing at the counter in a trance, waiting for him to come and wait on me. I guess I should be more evil, like those witches at the deli counter on Christmas Eve in Manhattan.
... or use a spider statuette and chase him out...
No! Yet another thing I did not know.
However, this is the only RPG I have ever even started to re-play without at least a year delay (ie enough time to forget most of it).
How many times have you gone through it? I was a little disappointed that I couldn't go back in and continue with my character, perhaps through the next level of the same set of maps (like in Diablo). That's one of the things I hated about Starcraft and Warcraft - starting out with nothing over and over and over again.