The reason I have not done this in Sense yet is I am not a fan of drill down dimensions, as stuff changes without the user explicitly requesting it to - I would go for allowing the user to pick which dimension they want every time.
You can use the translation function within the label expression of the dimension, as I put above. Just replace the label in single quotes with your translation code. I don't quite follow your translate code, but you would have something like:
The whole point of this approach is that it doesn't use a Sense drill down dimension. It uses a standard Sense dimension (without drill down) in which you then create your own pseudo drill down in code. This means the dynamic label is therefore available.