Well, I love a happy ending.
After completely disassembling the bike including taking the bottom bracket out (note to recent Q45 buyers: there was not even a single molecule of grease on the crank bolts nor the bottom bracket threads so you'd be wise to pull the cranks and the bottom bracket and grease everything up good; same with the headset bolt etc etc) and reassembling with extra grease and care to torque every single bolt just so, as well as dropping my gravel bike's rear wheel in the front fork of the Q to rule out spoke noise, the creaking/clicking was worse than ever and so was my groaning and moaning. Then while sitting on the bike, now able to replicate the sound while not riding by holding the brakes and putting pressure on the pedals, I noticed the boom flexing like crazy at the bottom bracket shell. What the heck? I tightened the bottom bracket shell clamps more and more, but the bike continued to make those awful noises. I had followed the instructions from the video to the 'T' and tried not to over tighten those clamps to keep from damaging the rubber grommets included on this year's clamps. But then I thought, neither my old Silvio 1.5 nor either of my Vendettas had rubber grommets there. So in near desperation i took them out and retightened the clamps as on the other bikes. Sat on the bike and tried to replicated the creaking. Hmmmm. Quiet. Took the bike for a spin up the street and back. Quiet as a mouse. Rode out again putting as many watts as I could muster into the pedals and the bike remained creak and click free. Hallelujah! After around 30 total hours of trying to ID the source of the creaking and knock it out, all I had to do was remove some grommets. Go figure.
Not sure what purpose those rubber grommets are supposed to serve but I can only hope taking them out causes no damage because I'm not putting them back. I was about ready to return the bike; indeed, if this was my first Cruzbike I would have already done so, but I've learned to trust and respect Cruzbike quality so I had to keep trying. Glad I did.
Now to get back to finding another solution for the water bottle problem. (hint: it came via UPS today. stay tuned)