I have a similar but different problem with Mansion Baron. I have two Sims with the mansion baron/have a home worth $50k aspiration. I move them in to a 50k house and one registers the aspiration but not the other. I tested a few different things just out of curiousity --
I tried moving them both before and after they were married, made no difference.
I tried it controlling first one sim, then the other when selecting the Household -> Move Household option on the computer. Made no difference it was still her that got the achievement and he did not.
I tried using the option "Move Out Household" from the Manage Worlds screen instead. Also made no difference.
Last but not least I moved them in to the house and then tried changing his aspiration to something else then back again. Nope. He's at 0/50,000 and she's got her aspiration fulfilled.
Interestingly enough, his sub condition was own 15 peices of art. That did register, he's at 5/15. He was at 0 before moving in, I reloaded and verified.