Healing his injury completely is a big milestone, but the temptation for him to return sooner than plan should be disregarded. While he's in Argentina, he's training hard as hell day in day out. You can be assured he's training all aspects of his play: strength, agility, technique, shooting, and most importantly he's building endurance. You could be built like a hulk yet still get injured as much as Adriano, the key to staying fit is durable muscles and lengthy training sessions prove that he's conditioning himself well.
Staying in Argentina to continue the planned recovery is probably 10x better than a hasty change. 12 hours per day working is improving him more than he would in Barcelona, plus he lives detached from all the pressure in Europe being focused and disciplined.