While the career outfits may not be categorized as formal (I can't remember) I do know you can use the clothing tool to "gank" any outfit a sim is wearing and add it too your sim's clothing inventory so they can use it at any time. Could try that too.
The clothing tool doesn't give me the option to select uniforms as formal attire, however, so sims won't change into them automatically (such as at weddings). Also, I loved that the hack only made the uniform option available to sims in the military career. I have no idea how to do that, and the tutorial doesn't even touch on it.
I appreciate the suggestions though.
I might be missing something, but I don't see the problem. The Sims will still only have the outfits from being in the Military career unless you unlock or clone the outfits and have someone purchase them.
I've opened up the file you attached and it does just look like a simple recategorization. I don't see anything that isn't a Property Set for an outfit and the only things that have been changed are the clothing categories. Although that does bring up the question as to why it doesn't work any longer. Are you certain you aren't experiencing some kind of conflict with another file?