Sorry, I'm late in replying, I got caught up in life's distractions. I suppose my original message wasn't clear enough; I was indeed trying to do what you have described here, and when I realised it wasn't possible, I tried to start over and build the body from scratch in Outfit Studio and replicate the character's body.
My challenge (and the reason why I asked for help) was to see the result in the game, because the body I made in the outfit and the one in the game did not match. I found out the culprit, though, it was SAM. There was an active 'morph' on the character that I did not remember doing. The morph was applied on top of the body I built and messing it up. After I reset everything, it started working again.
I wanted to post the result here, in case it might help someone else.