Nice puzzle idea and well presented. I enjoyed playing it...
It did seem a little too much down to luck though - if you happen to randomly pick a good couple of interrogations to start with, then it was quite easy, but start off unlucky then it seems near impossible to work out given the limited interrogations.
Perhaps a few more factors could have been introduced and the chance to gain more interrogations show how would have been nice for when you get stuck.
Nice entry though, interesting idea :)