Thanks for the advice (and the sympathy), Market. I never really intended to do this achievement in the first place. I tend to frown on just about any game that requires on outside reliance beyond a co-op partner to 100%. However, I ended up finding some random strangers who helped me get IPO, and all of the sudden CEO didn't seem so far off.
I decided to take on the challenge of going after it again. Only this time, I did a straight up grind-a-thon solo. Took me about 12hrs total (over the course of a week). For some reason, this damn game had that something special to make me do it again.
I'll update the original post so hopefully others don't fall victim to the same circumstances.