Here's my take...
Blue, I've read many of your threads, and believe me, I feel for you - I've been lucky over the years to have my own bands that I've started become fairly successful (as far as you can be successful playing locally in cover bands). I've also established many contacts along the journey so that if I had the need or want to find or start a new band, it would only take a few phone calls. I couldn't imagine starting from scratch and having to audition at this point in my life - more power to you for keeping at it! I wish you the best of luck in finding the right situation.
That said, I don't understand what you're doing here with THIS situation. Comments you've made makes it pretty clear that you're NOT interested in this band, so why give a deadline at all? Whether they tell you tomorrow or in 2 weeks, do you really want to play bass in this group? If you DON'T, I feel you should've just said "Thanks, but no thanks." And if you ARE still interested, then I would've let them finish their auditions and call, while at the same time kept looking for other options. You could either not say anything and wait and look, or even tell them that you're still looking (that would imply that they better grab you up if they liked you and don't want to lose you to someone else...)
I really don't understand why you felt you had to lie to force their decision if you don't really want to play with them anyways. If they call you back and say "Hey, we'll take you!", are you going to all of a sudden have a change of heart and WANT to be part of this group?
I'll tell you this - many years ago when I was putting together one of my 'start-up' bands (that's going on 20 years now...), we held auditions for a guitar player and finally found a decent player who seemed into the group. 4 months later, it was obvious that he wanted to go a completely different direction from what we were doing, and I confronted him at a rehearsal about it. His response was that he only took the gig to play with people and get better, but never wanted to play the music we were playing.
He got what he wanted out of it, and wasted all our time for 4 months - then we had to start auditioning again. To this day, I don't respect him for that, and if he ever popped up in/around something I was involved in, he'd be gone, or I'd pack it because I wouldn't work with this idiot again.
Just my experiences and thoughts....